Nodyn:Dyfynnu

Dogfennaeth nodyn[gweld] [golygu] [hanes] []

For the ^{[citation needed]} template, see {{citation needed}}.

The Citation template generates a citation for a book, periodical, contribution in a collective work, patent, or a web page. It determines the citation type by examining which parameters are used.

If invoked with the right parameters, this template produces output identical to that of the Cite templates, such as {{Cite book}} and {{Cite web}}. The default behavior sometimes differs from that of the Cite templates; for example, this template by default generates anchors for Harvard references whereas the Cite templates do not (although they can be made to do so), and this template by default uses commas to separate some fields that the Cite templates separate with periods (full stops).

The template should be inserted after punctuation, such as a period or comma.

All parameter names are lowercase.

Simple citation

This template gives the most commonly used attributes. You can copy the horizontal form or vertical form below and then add in extra attributes from the full list. Spacing and ordering is irrelevant.

{{Citation | last = | first = | year = | title = | publisher = | publication-place = | page = | url = | accessdate = }}

{{Citation | last = | first = | year = | title = | publisher = | publication-place = | page = | url = | accessdate = }}

• last: The author's surname or last name. Don't use with author.
• first: The author's first or given name(s).
• year: Year of authorship or publication. Mandatory for use with links from Template:Harvard citation, unless |date= specifies both month and year.
• title: Title of the work. Mandatory for web references.
• publisher: The name of the publisher. Omit terms such as Publishers, Co., Inc., Ltd., etc., but retain the words Books or Press.
  • publication-place (or place): The city of publication. If more than one town/city is listed on the title page, give the first one or the location of the publisher's head office.
• page: For use when one page is cited. Adds "p." before the page number. Do not use with pages.
• url: An url of an online location where the item can be found. If the url includes double quotes, these must be encoded as "%22".
  • accessdate: Date when the url was accessed.

Example

{{Citation | last = Turner | first = Orsamus | title = History of the pioneer settlement of Phelps and Gorham's purchase, and Morris' reserve | publisher = William Alling | place = Rochester, New York | year = 1851 | id = {{OL|7120924W}} }}

Turner, Orsamus (1851), History of the pioneer settlement of Phelps and Gorham's purchase, and Morris' reserve, Rochester, New York: William Alling, OL7120924W

Full citation parameters

These can be used for all types of publication except patents. All are optional and indentation is used simply to group related items — these may be mutually exclusive where indicated. Some hyphenated names can also be placed without hyphens.

{{Citation | author = | last = | first = | author2 = | last2 = | first2 = | author-link = | author2-link = | author-separator = | author-name-separator = | author-mask = | display-authors = | coauthors = | editor = | editor-last = | editor-first = | editor2 = | editor2-last = | editor2-first = | editor-link = | editor2-link = | others = | publication-date = | year = | month = | origyear = | title = | chapter = | chapter-url = | contribution = | contribution-url = | type = | journal = | periodical = | newspaper = | magazine = | work = | edition = | series = | volume = | issue = | publisher = | publication-place = | place = | language = | page = | pages = | nopp = | at = | id = | isbn = | issn = | oclc = | pmid = | pmc = | bibcode = | doi = | doi-inactive = | url = | accessdate = | format = | archiveurl = | archivedate = | quote = | laysummary = | laysource = | laydate = | separator = | postscript = | ref = }}

• author (or author1): The author's name. It is preferable to use the last/first attributes below for single or multiple authors.
  • last (or last1): The author's surname or last name.
  • first (or first1): The author's first or given name(s).
  • author2, last2, first2, up to author9 etc.: can be used for multiple authors– up to 8 will be shown before et al. is displayed
  • author-link: Title of an existing Wikipedia article about the first author (author2-link etc can also be used).
  • author-separator: override the default semi-colon that separates authors.
  • author-name-separator: override the default comma that separates authors' last and first names.
  • author-mask: See #Additional parameters, below.
  • display-authors: Truncate the list of authors at an arbitrary point with "et al". You should still include the first 9 authors to allow metadata to be generated. n.b. operates only when the authors are given using either several |authorn=, or several |lastn=|firstn= pairs; does not affect the display of a list in either |authors= or |coauthors=.
  • lastauthoramp: If supplied, whether or not assigned a value, places an ampersand (&) before the last name of final author, if more than one author is supplied. Recommended usage is lastauthoramp = yes.
  • coauthors: Names of additional author(s) can be given but author2 or last2, first2 is preferred.
• editor: Name of editor, placed after date with ,ed. Not required for periodicals.
  • editor-link: link to article about the editor
• others: Any other associated people, e.g., foreword, placed after editor.
• publication-date (or date): Date of publication.
  • date: Date of authorship, if different from date of publication. If only date is used, it will be treated as the date of publication.
  • year: Year of authorship or publication. (Mandatory for use with links from Template:Harvard citation. In some situations, the template may be able to derive a year from the full date.)
    • month: Month of publication (ignored if the date field is used).
  • origyear: Year of first publication, if different.
• title: Title of the book or article in a periodical. If the title includes [square brackets], these must be encoded as "[" for "[" and "]" for "]"
• chapter or contribution: title of the chapter or part of a publication will be put in quotes.
  • chapter-url or contribution-url: use to add a link to the chapter or contribution title.
• type: An optional field which can be used to provide additional information about a publication type. The content appears in parentheses following the title. If the publication is a thesis or dissertation, the type might be specified as type = PhD thesis, If the publication is an audiobook on compact disk, the type might be specified as type = CD.
  • journal or periodical or newspaper or magazine or work: Name of the journal or periodical.
• edition: Number or name of the edition, if not the first; for example: edition = 2nd.
  • series: The book series of which this book is a part.
  • volume: The volume number of a multi-volume book.
  • issue: Issue number of a periodical.
• publisher: The name of the publisher. Omit terms such as Publishers, Co., Inc., Ltd., etc., but retain the words Books or Press. Not needed if ISSN or DOI used.
  • publication-place (or place): The city of publication. If more than one town/city is listed on the title page, give the first one or the location of the publisher's head office. If the city is not well-known, you may add a county, region, or state. States in the U.S. are denoted by a two-letter code; for example: place = Paris, TX (no period at the end). Where the publisher is a university and the place or location is included in the name of the university, do not use this parameter.
    • place or location: City in which the work was made, if different from the city of publication. If only place is used, it will be treated as the city of publication.
• language: If not English. e.g., Finnish.
• page: For use when one page is cited. Adds "p." before the page number. Do not use with pages.
  • pages: For use when multiple pages are cited. Adds "pp." before the page numbers. Do not use with page.
  • nopp: if set to any value, page = /pages = do not generate 'p.' or 'pp.'. E.g. nopp = true. Using at = has the same effect.
  • at: Position within the resource when |page=/|pages= is inappropriate or insufficient. This parameter is ignored if |page=/|pages= is specified. Examples of usage of |at=: |at=para. 14 (when citing a source without page numbers), |at=02:56 (a film or audio timestamp), |at=no. 456 (something in a numbered list), |at=p. 6, col. 2 (for a page and a column because "column" is not a Citation template parameter), or |at=sec. F pp. 4–6 (for a section and a page within the section, "section" not being a parameter).

• id: A unique identifier, used where none of the specialized identifiers are applicable; wikilink or use a template as applicable.

• arxiv: ArXiv.
• asin: Amazon Standard Identification Number.
  • asin-tld: ASIN top-level domain for Amazon sites other than the US; valid values: co.jp, co.uk, ca, cn, fr, de, it, es
• bibcode: Bibcode; used by a number of astronomical data systems; example: 1924MNRAS..84..308E.
• doi: Digital object identifier; example: 10.1038/news070508-7; checked to ensure it begins with 10.; if not an error shows and the page is placed in Category:Pages with DOI errors.
  • doi_brokendate: Date the DOI is broken; use the same format as other dates in the article.
• isbn: International Standard Book Number such as 978-0812695939; see Wikipedia:ISBN and ISBN. Dashes in the ISBN are optional, but preferred. Use the 13-digit ISBN where possible; this can normally be found beneath the barcode as a number beginning 978 or 979. For sources with the older 9 digit SBN system, prefix the number with a zero; thus SBN 812695-93-3 should be entered as |isbn=0812695-93-3.
• issn: International Standard Serial Number; eight characters may be split into two groups of four using a hyphen, but not an N-dash or a space.
• jfm: Jahrbuch über die Fortschritte der Mathematik.
• jstor: JSTOR abstract.
• lccn: Library of Congress Control Number.
• mr: Mathematical Reviews.
• oclc: Online Computer Library Center.
• ol: Open Library.
• osti: Office of Scientific and Technical Information.
• pmc: PubMed Central article number for full-text free repository of an article.
• pmid: PubMed Unique Identifier.
• rfc: Request for Comments.
• ssrn: Social Science Research Network.
• zbl: Zentralblatt MATH.

• url: URL of an online location where the text of the publication can be found. Cannot be used if title is wikilinked. If applicable, the link may point to the specific page(s) referenced. Do not link to any commercial booksellers such as Amazon.com; see WP:PAGELINKS.
  • accessdate: Full date when URL was accessed; use the same format as other access and archive dates in the citations; do not wikilink. Can be hidden by registered editors.
  • archiveurl: The URL of an archived copy of a web page, if or in case the url becomes unavailable. Typically used to refer to services like WebCite and the Internet Archive; requires archivedate.
    • archivedate: Date when the item was archived; use the same format as other access and archive dates in the citations; do not wikilink. Displays preceded by "archived from the original on".
    • deadurl: When the URL is still live, but preemptively archived, then set |deadurl=no. This changes the display order with the title retaining the original link and the archive linked at the end.
  • template doc demo: The archive parameters have error checking to ensure that all the required parameters are included, else {{citation error}} is invoked. On errors, main, help and template pages are placed into Category:Articles with incorrect citation syntax. Set |template doc demo=true to disable categorization; mainly used for documentation where the error is demonstrated.
• format: Format of the work referred to by url; examples: PDF, DOC, XLS; HTML is implied and should not be specified; displayed in parentheses after title. Does not change external link icon.

URLs must begin with a supported URI scheme: http:// and https:// will be supported by all browsers; irc://, ircs://, ftp://, news:, mailto: and gopher:// will require a plugin or an external application and should normally be avoided. IPv6 host-names are currently not supported.

If URLs in citation template parameters contain certain characters they will display and link incorrectly. Those characters need to be percent-encoded. For example, a space must be replaced by %20. To encode the URL, replace these characters:

sp	"	'	<	>	[	]	|	}
%20	%22	%27	%3c	%3e	%5b	%5d	%7c	%7d

Single apostrophes do not need to be encoded; but unencoded multiples will be parsed as italic or bold markup. Single curly closing braces also do not need to be encoded; but an unencoded pair will be parsed as the double closing braces for the template transclusion.

• separator: specifies the punctuation mark used to separate certain fields. This defaults to a comma; the Citation Style 1 family of templates uses a period.
• laysummary: url of a lay summary of a technical article, which could be in a popular science magazine or newspaper.
  • laysource: Name of the source, e.g., The Guardian (UK newspaper) or New Scientist.
  • laydate: The date of publication or, where this is not available, date of retrieval of the lay summary.
• postscript: Set terminal punctuation. Omit or leave blank to remove the trailing full stop. Punctuation specified by this parameter will appear within the cite span, and consequently before any icons added by metadata-using software, e.g., library browser plugins. Hence this parameter should be used instead of manually appending data to the citation. This parameter is ignored if |quote= is specified, when |postscript=. is forced.
• ref: An explicit ID for Harvard references; see Anchors for Harvard references

Examples

Books

Three authors, a volume, and an edition. Ampersand (&) forced before final author's name.

{{Citation | last1 = Lincoln | first1 = A. | last2 = Washington | first2 = G. | last3 = Adams | first3 = J. | lastauthoramp = yes | title = All the Presidents' Names | publisher = The Pentagon | place = Home Base, New York | volume = XII | edition = 2nd | year = 2007 }}

Lincoln, A.; Washington, G. & Adams, J. (2007), All the Presidents' Names, XII (2nd ed.), Home Base, New York: The Pentagon

Web

Web page	{{Citation | url = http://nrhp.focus.nps.gov | title = NPS Focus | work = National Register of Historic Places | publisher = [[National Park Service]] | accessdate = November 30, 2010 }}	"NPS Focus", National Register of Historic Places (National Park Service), http://nrhp.focus.nps.gov, adalwyd November 30, 2010
Archived page	{{Citation | url = http://liftoff.msfc.nasa.gov/ academy/space/atmosphere.html | title = Earth's Atmosphere | accessdate = October 25, 2007 | publisher = [[National Aeronautics and Space Administration]] | year = 1995 | author = NASA | archiveurl = http://web.archive.org/web/20071013232332/ http://liftoff.msfc.nasa.gov/academy/space/atmosphere.html | archivedate = October 13, 2007 }}	NASA (1995), Earth's Atmosphere, National Aeronautics and Space Administration, archifwyd o y gwreiddiol ar October 13, 2007, http://web.archive.org/web/20071013232332/http://liftoff.msfc.nasa.gov/academy/space/atmosphere.html, adalwyd October 25, 2007

Journals, newspapers, magazines, or other periodicals

Journal article	{{Citation | last = Hill | first = Marvin S. | title = Joseph Smith and the 1826 Trial: New Evidence and New Difficulties | journal = BYU Studies | volume = 12 | issue = 2 | year = 1976 | pages = 1–8 | url = https://byustudies.byu.edu/ shop/PDFSRC/12.2Hill.pdf }}	Hill, Marvin S. (1976), "Joseph Smith and the 1826 Trial: New Evidence and New Difficulties", BYU Studies 12 (2): 1–8, https://byustudies.byu.edu/shop/PDFSRC/12.2Hill.pdf
Journal article with multiple authors and identifier	{{Citation | last1 = Mandelkern | first1 = M, | last2 = Elias | first2 = J, | last3 = Eden | first3 = D, | last4 = Crothers | first4 = D | display-authors = 2 | title = The dimensions of DNA in solution | journal = J Mol Biol | volume = 152 | issue = 1 | pages = 153–61 | year = 1981 | pmid = 7338906 | doi = 10.1016/0022-2836(81)90099-1 }}	Mandelkern, M,; Elias, J, et al. (1981), "The dimensions of DNA in solution", J Mol Biol 152 (1): 153–61, doi:10.1016/0022-2836(81)90099-1, PMID 7338906
Newspaper article	{{Citation | last = Smith | first = Joseph III | author-link = Joseph Smith III | title = Last Testimony of Sister Emma | newspaper = The Saints' Herald | publication-place = Plano, IL | volume = 26 | issue = 19 | date = October 1, 1879 | year = 1879 | month = October | page = 289 | url = http://www.sidneyrigdon.com/ dbroadhu/IL/sain1872.htm#100179 }}	Smith, Joseph III (October 1, 1879), "Last Testimony of Sister Emma", The Saints' Herald (Plano, IL) 26 (19): 289, http://www.sidneyrigdon.com/dbroadhu/IL/sain1872.htm#100179
Conference paper	{{Citation | last = Sullivan | first = D.B. | contribution = Time and frequency measurement at NIST: The first 100 years | year = 2001 | title = 2001 IEEE Int'l Frequency Control Symp. | publisher = National Institute of Standards and Technology | url = http://tf.nist.gov/timefreq/ general/pdf/1485.pdf | format = PDF }}	Sullivan, D.B. (2001), "Time and frequency measurement at NIST: The first 100 years" (PDF), 2001 IEEE Int'l Frequency Control Symp., National Institute of Standards and Technology, http://tf.nist.gov/timefreq/general/pdf/1485.pdf

Parts of books, including encyclopedia articles

Manuscript published in an edited compilation	{{Citation | last = Bidamon | first = Emma Smith | author-link = Emma Hale Smith | chapter = Letter to Emma S. Pilgrim | date = March 27, 1876 | year = 1876 | editor-last = Vogel | editor-first = Dan | title = Early Mormon Documents | volume = 1 | publisher = Signature Books | publication-date = 1996 | isbn = 1–56085–072–8 }}	Bidamon, Emma Smith (March 27, 1876), "Letter to Emma S. Pilgrim", in Vogel, Dan, Early Mormon Documents, 1, Signature Books, 1996, ISBN 1–56085–072–8
Work with an editor but no author	{{Citation | editor-last = Vogel | editor-first = Dan | title = Early Mormon Documents | volume = 1 | publisher = Signature Books | publication-date = 1996 | isbn = 1–56085–072–8 }}	Vogel, Dan, ed. (1996), Early Mormon Documents, 1, Signature Books, ISBN 1–56085–072–8
Encyclopedia article by a named author	{{Citation | last = Kramer | first = Martin | author-link = Martin Kramer | contribution = Bernard Lewis | editor-last = Boyd | editor-first = Kelley | title = Encyclopedia of Historians and Historical Writing | volume = 1 | pages = 719–720 | publisher = Fitzroy Dearborn | place = London | publication-date = 1999 | contribution-url = http:// www.geocities.com/martinkramerorg/ BernardLewis.htm }}	Kramer, Martin (1999), "Bernard Lewis", in Boyd, Kelley, Encyclopedia of Historians and Historical Writing, 1, London: Fitzroy Dearborn, pp. 719–720, http://www.geocities.com/martinkramerorg/BernardLewis.htm
Encyclopedia article with no named author	{{Citation | contribution = Bernard Lewis | editor-last = Boyd | editor-first = Kelley | title = Encyclopedia of Historians and Historical Writing | volume = 1 | pages = 719–720 | publisher = Fitzroy Dearborn | place = London | year = 1999 | contribution-url = http:// www.geocities.com/martinkramerorg/ BernardLewis.htm }}	Boyd, Kelley, ed. (1999), "Bernard Lewis", Encyclopedia of Historians and Historical Writing, 1, London: Fitzroy Dearborn, pp. 719–720, http://www.geocities.com/martinkramerorg/BernardLewis.htm

Republications, or edited quotations in a periodical article

Manuscript edited and published in a journal	{{Citation | last = Knight | first = Joseph, Sr. | year = 1833 | editor-last = Jessee | editor-first = Dean | title = Joseph Knight's Recollection of Early Mormon History | journal = BYU Studies | volume = 17 | issue = 1 | publication-date = 1976 | pages = 35 | url = https://byustudies.byu.edu/ shop/PDFSRC/17.1Jessee.pdf }}	Knight, Joseph, Sr. (1833), Jessee, Dean, ed., "Joseph Knight's Recollection of Early Mormon History", BYU Studies 17 (1): 35, 1976, https://byustudies.byu.edu/shop/PDFSRC/17.1Jessee.pdf
Manuscript written at one date and place, then published in a periodical at a different date and place with commentary by the editor.	{{Citation | last = Klingensmith | first = Philip | contribution = Affidavit | year = 1872 | date = September 5, 1872 | place = Lincoln County, Nevada | title = Mountain Meadows Massacre | editor-last = Toohy | editor-first = Dennis J. | journal = Corinne Daily Reporter | publication-date = September 24, 1872 | publication-place = Corinne, Utah | volume = 5 | issue = 252 | pages = 1 | contribution-url = http:// udn.lib.utah.edu/u?/corinne,5359 }}	Klingensmith, Philip (September 5, 1872), Affidavit, written at Lincoln County, Nevada, in Toohy, Dennis J., "Mountain Meadows Massacre", Corinne Daily Reporter (Corinne, Utah) 5 (252): 1, September 24, 1872, http://udn.lib.utah.edu/u?/corinne,5359

Press release

Press release with quotation

{{Cite press release | url = http://www.apple.com/pr/ library/2010/04/05ipad.html | title = Apple Sells Over 300,000 iPads First Day | publisher = Apple Inc | accessdate = April 10, 2010 | quote = in the US as of midnight Saturday, April 3}}

"Apple Sells Over 300,000 iPads First Day" (Press release). Apple Inc. http://www.apple.com/pr/library/2010/04/05ipad.html. Adalwyd April 10, 2010. "in the US as of midnight Saturday, April 3"

Citing patents

Parameters (all are optional)

{{Citation | inventor-last = | inventor-first = | inventorlink = | inventor2-last = | inventor2-first = | inventorlink2 = | publication-date = | issue-date = | title = | country-code = | description = | patent-number = }}

inventor-last (or inventor1-last): The inventor's surname or last name. inventor-first (or inventor1-first): The inventor's first or given name(s). inventorlink (or inventorlink1): Title of an existing Wikipedia article about the first inventor. inventor2-last, inventor3-last, inventor4-last: The second, third, and fourth authors' surname or last name, if applicable. inventor2-first, inventor3-first, inventor4-first: The second, third, and fourth inventors' first or given name(s), if applicable. inventorlink2, inventorlink3, inventorlink4: Title of an existing Wikipedia article about the second, third, and fourth inventor, if applicable. publication-date: Date of publication or filing. issue-date (or date): Date patent was issued by patent agency. title: Title of the patent. If the title includes [square brackets], these must be encoded as "[" for "[" and "]" for "]" country-code: Two-letter abbreviation of the country issuing the patent. description: Type of patent; shown between country code and number. patent-number: The number of the patent.

Examples

United States patent with multiple inventors

{{Citation | inventor1-last = Degermark | inventor1-first = Mikael | inventor2-last = Brodnik | inventor2-first = Andrej | inventor3-last = Carlsson | inventor3-first = Svante | inventor4-last = Pink | inventor4-first = Stephen | title = Fast routing lookup system using complete prefix tree, bit vector, and pointers in a routing table for determining where to route IP datagrams | issue-date = 2001 | patent-number = 6266706 | country-code = US}}

US 6266706, Nodyn:Citation/authors, "Fast routing lookup system using complete prefix tree, bit vector, and pointers in a routing table for determining where to route IP datagrams", issued 2001

Anchored citations

This template can generate a citation that can be combined with shortened footnotes or parenthetical referencing. It does this by creating an HTML anchor containing an ID. The special parameter |ref=harv generates an ID suitable for Harvard referencing templates such as {{harv}} as specified in the next section; this is the default for the {{citation}} template. If an empty |ref= is given, no anchor is generated; this is the default for the Cite templates such as {{cite book}} and {{cite news}}. You can also specify the ID directly, using the |ref=ID parameter. For example, suppose an article's References section contains the markup:

• {{Citation | author = Sigmund Freud | title=Civilization and Its Discontents | year = 1930 | ref = CivDis}}

which generates the citation:

• Sigmund Freud (1930), Civilization and Its Discontents

Then, the markup "([[#CivDis|Freud 1930]])" generates a parenthetical reference "(Freud 1930)" containing a wikilink to the citation (try clicking on the wikilink).

Anchors for Harvard referencing templates

IDs compatible with Harvard referencing templates such as {{harv}} are computed from the last names of the authors and the year of the cited source. For example, the markup "{{harv|Wright|Evans|1851|p = ix}}" generates the Harvard reference "(Wright & Evans 1851, p. ix)", which wikilinks to the citation whose markup and appearance are shown below:

• {{Citation | last1 = Wright | first1 = Thomas | last2 = Evans | first2 = R.H. | title = Historical and Descriptive Account of the Caricatures of James Gillray | location = London | publisher = Henry G. Bohn | year = 1851 | oclc = 59510372 }}
• Wright, Thomas; Evans, R.H. (1851), Historical and Descriptive Account of the Caricatures of James Gillray, London: Henry G. Bohn, OCLC 59510372

In this example the {{citation}} template defines, and the {{harv}} template uses, the HTML ID "CITEREFWrightEvans1851", composed by concatenating the string "CITEREF" with the last names of the authors and the year. The {{harvid}} template can be used to generate such IDs, for example, {{harvid|Wright|Evans|1851}} generates "CITEREFWrightEvans1851".

Related methods which leave only a number in the text are to use the {{harvnb}} template enclosed in the <ref></ref> html code, or to use the {{sfn}} template alone. The example above would be <ref>{{harvnb|Wright|Evans|1851|p = ix}}</ref> or {{sfn|Wright|Evans|1851|p = ix}} both of which generate a footnote, such as

17. Wright & Evans 1851, t. ix

The names of only the first four authors are used; other author names are not concatenated to the ID. If no author names are given, editor names are used instead. For patents, inventor names are used instead of authors or editors. If these names are not given, this template does not generate an anchor.

Last names are used, as specified by the parameters |last1= (or |last=), |last2=, |last3=, and |last4=, and similarly for |editor1-last= etc. and for |inventor1-last= etc. If a full name is given but no last name is specified, this template falls back on the full name, but this usage is not recommended. For example, in "{{Citation | author = Sigmund Freud | title = The Ego and the Id | year = 1923}}" no last name is given, so this citation cannot be combined with the Harvard reference "{{harv|Freud|1923}}". To make these {{citation}} and {{harv}} invocations compatible, either replace "|author=Sigmund Freud" with "|first=Sigmund |last=Freud", or add "|ref={{harvid|Freud|1923}}" to the {{citation}} invocation, or add the same ref parameter (say, "|ref=EgoId") to both the {{citation}} and the {{harv}} invocations.

Similarly, the year is used, as specified by |year=. If no year is given, this template attempts to derive the year from |date= (or, if no date is given, from |publication-date=) by applying the MediaWiki#time function. This heuristic works with many common date formats (American, International and ISO standard format YYYY-MM-DD as listed in WP:MOS), but may not work as expected with other formats, so when in doubt it may be safer to use |year=. Note that if only a year, say 2005, is known you must use |year=2005 rather than |date=2005.

IDs must be unique

Names, years, and hand-specified IDs must be chosen so that the IDs are unique within a page; otherwise the HTML will not conform to the W3C standards, and any references to the citations will not work reliably. For example, suppose a page contains the following two citations with {{harv}}-compatible IDs:

• Montes, G; Halterman, JS (2008a), "Association of childhood autism spectrum disorders and loss of family income", Pediatrics 121 (4): e821–6, doi:10.1542/peds.2007-1594, PMID 18381511, http://pediatrics.aappublications.org/cgi/content/full/121/4/e821
• Montes, G; Halterman, JS (2008b), "Child care problems and employment among families with preschool-aged children with autism in the United States", Pediatrics 122 (1): e202–8, doi:10.1542/peds.2007-3037, PMID 18595965, http://pediatrics.aappublications.org/cgi/content/full/122/1/e202

If these citations were altered to say "2008" rather than "2008a" and "2008b", the resulting page would not work, because the two different citations would both attempt to use the ID "CITEREFMontesHalterman2008". To avoid this problem, distinguish the citations by appending suffixes to the years, e.g., "|year=2008a" and "|year=2008b", as was done above. Any Harvard references to these citations should use years with the same suffixes.

It is good practice to verify that a page does not contain duplicate IDs by using the W3C Markup Validation Service; see External links.

Dates

Tools

See Wikipedia:Citing sources#Citation templates and tools for a list of tools that can help create a reference in the "citation" format.

TemplateData

The Citation template generates a citation for a book, periodical, contribution in a collective work, patent, or a web page. It determines the citation type by examining which parameters are used.

Paramedrau'r nodyn[Edit template data]

Paramedr		Disgrifiad	Math	Statws
Last name	last author author1 authors last1	The surname of the author; don't wikilink, use 'authorlink'; can suffix with a numeral to add additional authors	Llinell	suggested
First name	first first1	Given or first name, middle names, or initials of the author; don't wikilink, use 'authorlink'; can suffix with a numeral to add additional authors	Llinell	suggested
title of source	title	Title of source; displays in italics.	Llinyn	angenrheidiol
date of source	date	Full date of source being referenced in the same format as other publication dates in the citations.[1] Do not wikilink. Displays after the authors and enclosed in parentheses. If there is no author, then displays after publisher.	Llinyn	dewisol
url of source	url	URL of an online location where the text of the publication can be found.	Llinyn	dewisol
Work	work journal website newspaper magazine encyclopedia encyclopaedia dictionary mailinglist	Name of the work in which the cited title is found	Llinyn	dewisol
Volume	volume	For one publication published in several volumes	Llinell	suggested
Issue	issue number	Issue number	Llinyn	dewisol
Page	page	Page in the source that supports the content; displays after 'p.'	Llinell	dewisol
Pages	pages	Pages in the source that support the content (not an indication of the number of pages in the source; displays after 'pp.'	Llinell	suggested
Patent Number	patent-number	dim disgrifiad	Llinyn	dewisol
Description	description	Type of patent; shown between country code and number.	Llinyn	dewisol
Publication Date	publication-date pubdate	Date of publication when different from the date the work was written. Displays only if year or date are defined and only if different, else publication-date is used and displayed as date. Use the same format as other dates in the article; do not wikilink. Follows publisher; if work is not defined, then publication-date is preceded by "published" and enclosed in parenthesis.	Llinyn	dewisol
Issue Date	issue-date	Date patent was issued by patent agency.	Llinyn	dewisol
Date format	df	Sets rendered dates to the specified format	Llinyn	dewisol
Year of publication	year	Year of the source being referenced; recommended only when date parameter format is YYYY-MM-DD and a CITEREF disambiguator is needed	Rhif	dewisol
Postscript	postscript	Controls the closing punctuation for a citation; defaults to a period (.); for no terminating punctuation, specify |postscript=none – leaving |postscript= empty is the same as omitting it, but is ambiguous. Ignored if quote is defined.	Llinyn	dewisol
Editor last name	editor-last editor editor-surname editor-last1 editor-surname1 editor1 editor1-last editor1-surname editors	The surname of the editor; don't wikilink, use 'editor-link'; can suffix with a numeral to add additional editors	Anhysbys	dewisol
Editor first name	editor-first editor-first1 editor-given1 editor1-first editor1-given	The surname of the editor; don't wikilink, use 'editor-link'; can suffix with a numeral to add additional editors	Anhysbys	dewisol
Author Mask	author-mask authormask	Replaces the name of the first author with em dashes or text. Set author-mask to a numeric value n to set the dash n em spaces wide; set author-mask to a text value to display the text without a trailing author separator; for example, "with". You must still include the values for all authors for metadata purposes. Primarily intended for use with bibliographies or bibliography styles where multiple works by a single author are listed sequentially such as shortened footnotes. Do not use in a list generated by {{reflist}}, <references /> or similar as there is no control of the order in which references are displayed. You can also use editor-mask and translator-mask in the same way.	Llinyn	dewisol
Original year	orig-year origyear	Original year of publication; provide specifics	Rhif	dewisol
Translated title	trans-title trans_title	An English language title, if the source cited is in a foreign language; 'language' is recommended	Cynnwys	dewisol
Translated chapter title	trans-chapter trans_chapter	An English language chapter title, if the source cited is in a foreign language; 'language' is recommended	Cynnwys	dewisol
Type	type	Additional information about the media type of the source; format in sentence case	Cynnwys	dewisol
Archive URL	archive-url archiveurl	The URL of an archived copy of a web page, if or in case the URL becomes unavailable; requires 'archivedate'	Llinell	dewisol
Dead URL	dead-url deadurl	If set to 'no', the title display is adjusted; useful for when the URL is archived preemptively but still live	Llinell	dewisol
Series	series version	Series identifier when the source is part of a series, such as a book series or a journal; alias of 'version'	Cynnwys	dewisol
periodical	periodical	dim disgrifiad	Llinyn	dewisol
At	at	May be used instead of 'page' or 'pages' where a page number is inappropriate or insufficient	Llinell	dewisol
No pp	nopp	Set to 'y' to suppress the 'p.' or 'pp.' display with 'page' or 'pages' when inappropriate (such as 'Front cover')	Llinell	dewisol
Chapter	chapter	The chapter heading of the source	Llinyn	dewisol
contribution	contribution	dim disgrifiad	Llinyn	dewisol
chapter-url	chapter-url chapterurl	dim disgrifiad	Llinyn	dewisol
contribution-url	contribution-url	dim disgrifiad	Llinyn	dewisol
chapter-format	chapter-format	dim disgrifiad	Llinyn	dewisol
others	others	dim disgrifiad	Llinyn	dewisol
Edition	edition	When the publication has more than one edition; for example: '2nd', 'Revised' etc.; suffixed with ' ed.'	Llinell	dewisol
Location of publication	place location	Geographical place of publication; usually not wikilinked	Llinyn	dewisol
Place of publication	publication-place	Publication place shows after title; if 'place' or 'location' are also given, they are displayed before the title prefixed with 'written at'	Cynnwys	dewisol
Publisher	publisher	Name of the publisher; displays after title	Cynnwys	dewisol
in	in	dim disgrifiad	Llinyn	dewisol
Language	language	The language in which the source is written, if not English; use the full language name; do not use icons or templates	Cynnwys	dewisol
Format	format	Format of the work referred to by 'url' ('url' is required when using 'format'); examples: PDF, DOC, XLS; do not specify HTML	Cynnwys	dewisol
arXiv identifier	arxiv	An identifier for arXive electronic preprints of scientific papers	Llinell	dewisol
ASIN	asin ASIN	Amazon Standard Identification Number; 10 characters	Llinell	dewisol
ASIN TLD	asin-tld	ASIN top-level domain for Amazon sites other than the US	Llinell	dewisol
Bibcode	bibcode	Bibliographic Reference Code (REFCODE); 19 characters	Llinell	dewisol
biorXiv	biorxiv	biorXiv identifier; 6 digits	Llinell	dewisol
CiteSeerX	citeseerx	CiteSeerX identifier; found after the 'doi=' query parameter	Llinell	dewisol
DOI	doi DOI	Digital Object Identifier; begins with '10.'	Llinyn	dewisol
doi_inactivedate	doi_inactivedate	dim disgrifiad	Llinyn	dewisol
DOI broken date	doi-broken-date	The date that the DOI was determined to be broken	Dyddiad	dewisol
ISBN	isbn	International Standard Book Number; use the 13-digit ISBN where possible	Llinell	dewisol
ISSN	issn	International Standard Serial Number (print); 8 characters; usually split into two groups of four using a hyphen	Llinell	dewisol
eISSN	eissn	International Standard Serial Number (online); 8 characters; usually split into two groups of four using a hyphen	Llinell	dewisol
jfm code	jfm	Jahrbuch über die Fortschritte der Mathematik classification code	Llinell	dewisol
JSTOR	jstor	JSTOR identifier	Llinell	dewisol
LCCN	lccn	Library of Congress Control Number	Llinell	dewisol
MR	mr	Mathematical Reviews identifier	Llinell	dewisol
OCLC	oclc	Online Computer Library Center number	Rhif	dewisol
OL	ol	Open Library identifier	Llinell	dewisol
OSTI	osti	Office of Scientific and Technical Information identifier	Llinell	dewisol
PMC	pmc	PubMed Center article number	Rhif	dewisol
PMID	pmid	PubMed Unique Identifier	Llinell	dewisol
RFC	rfc	Request for Comments number	Rhif	dewisol
SSRN	ssrn	Social Science Research Network	Llinell	dewisol
Zbl	zbl	Zentralblatt MATH journal identifier	Llinell	dewisol
id	id	A unique identifier used where none of the specialized ones are applicable	Llinell	dewisol
Quote	quote	Relevant text quoted from the source; displays last, enclosed in quotes; needs to include terminating punctuation	Cynnwys	dewisol
Ref	ref	An anchor identifier; can be made the target of wikilinks to full references; special value 'harv' generates an anchor suitable for the harv and sfn templates	Llinell	dewisol
URL access date	access-date accessdate	The full date when the original URL was accessed; do not wikilink	Dyddiad	dewisol
Lay URL	laysummary layurl lay-url	URL link to a non-technical summary or review of the source	Llinell	dewisol
Lay source	lay-source laysource	Name of the source of the laysummary; displays in italics, preceded by an en dash	Llinyn	dewisol
Lay date	lay-date laydate	Date of the summary; displays in parentheses	Dyddiad	dewisol
Author name separator	author-name-separator	Changes the separator between last and first names; defaults to a comma and space; a space must be encoded as &#32; Yn ddiofyn ,	Llinell	dewisol
Last author ampersand	last-author-amp lastauthoramp	When set to any value, changes the separator between the last two names of the author list to 'space ampersand space'	Boole	dewisol
Display authors	displayauthors display-authors	number of authors to display before 'et al.' is used;	Rhif	dewisol
Archive date	archive-date archivedate	Date when the original URL was archived; do not wikilink	Dyddiad	dewisol
inventor-last	inventor-last inventor-surname inventor-last1 inventor invent-1 invent1 inventor1-surname	dim disgrifiad	Llinyn	dewisol
inventor2-last	inventor2-last inventor2 invent2 inventor2-surname	dim disgrifiad	Llinyn	dewisol
inventor3-last	inventor3-last inventor3 invent3 inventor3-surname	dim disgrifiad	Llinyn	dewisol
inventor4-last	inventor4-last inventor4 invent4 inventor4-surname	dim disgrifiad	Llinyn	dewisol
inventor-first	inventor-first inventor1-first inventor-given inventor1-given	dim disgrifiad	Llinyn	dewisol
inventor2-first	inventor2-first inventor2-given	dim disgrifiad	Llinyn	dewisol
inventor3-first	inventor3-first inventor3-given	dim disgrifiad	Llinyn	dewisol
inventor4-first	inventor4-first inventor4-given	dim disgrifiad	Llinyn	dewisol
inventorlink	inventorlink inventorlink1	dim disgrifiad	Llinyn	dewisol
inventorlink2	inventorlink2	dim disgrifiad	Llinyn	dewisol
inventorlink3	inventorlink3	dim disgrifiad	Llinyn	dewisol
inventorlink4	inventorlink4	dim disgrifiad	Llinyn	dewisol
Last name 2	last2 author2 surname2	The surname of the second author; don't wikilink, use 'authorlink2'.	Llinell	dewisol
First name 2	first2 given2	Given or first name, middle names, or initials of the second author; don't wikilink.	Llinell	dewisol
Last name 3	last3 author3 surname3	The surname of the third author; don't wikilink, use 'authorlink3'.	Llinell	dewisol
First name 3	first3 given3	Given or first name, middle names, or initials of the third author; don't wikilink.	Llinell	dewisol
Last name 4	last4 author4 surname4	The surname of the forth author; don't wikilink, use 'authorlink4'.	Llinell	dewisol
First name 4	first4 given4	Given or first name, middle names, or initials of the forth author; don't wikilink.	Llinell	dewisol
Last name 5	last5 author5 surname5	The surname of the fifth author; don't wikilink, use 'authorlink5'.	Llinell	dewisol
First name 5	first5 given5	Given or first name, middle names, or initials of the fifth author; don't wikilink.	Llinell	dewisol
Last name 6	last6 author6 surname6	The surname of the sixth author; don't wikilink, use 'authorlink6'.	Llinell	dewisol
First name 6	first6	Given or first name, middle names, or initials of the sixth author; don't wikilink.	Llinell	dewisol
Last name 7	last7 author7 surname7	The surname of the seventh author; don't wikilink, use 'authorlink7'.	Llinell	dewisol
First name 7	first7 given7	Given or first name, middle names, or initials of the seventh author; don't wikilink.	Llinell	dewisol
Last name 8	last8 author8 surname8	The surname of the eighth author; don't wikilink, use 'authorlink8'.	Llinell	dewisol
First name 8	first8 given8	Given or first name, middle names, or initials of the eighth author; don't wikilink.	Llinell	dewisol
Last name 9	last9 author9 surname9	The surname of the ninth author; don't wikilink, use 'authorlink9'. If nine authors are defined, then only eight will show and 'et al.' will show in place of the last author.	Llinell	dewisol
First name 9	first9 given9	Given or first name, middle names, or initials of the ninth author; don't wikilink.	Llinell	dewisol
Author link	author-link authorlink author1-link authorlink1	Title of existing Wikipedia article about the author; can suffix with a numeral to add additional authors	Page name	dewisol
Author link 2	author-link2 author2-link authorlink2	Title of existing Wikipedia article about the second author.	Page name	dewisol
Author link 3	author-link3 author3-link authorlink3	Title of existing Wikipedia article about the third author.	Page name	dewisol
Author link 4	author-link4 author4-link authorlink4	Title of existing Wikipedia article about the forth author.	Page name	dewisol
Author link 5	author-link5 author5-link authorlink5	Title of existing Wikipedia article about the sixth author.	Page name	dewisol
Author link 6	author-link6 author6-link authorlink6	Title of existing Wikipedia article about the sixth author.	Page name	dewisol
Author link 7	author-link7 author7-link authorlink7	Title of existing Wikipedia article about the seventh author.	Page name	dewisol
Author link 8	author-link8 author8-link authorlink8	Title of existing Wikipedia article about the eighth author.	Page name	dewisol
Author link 9	author-link9 author9-link authorlink9	Title of existing Wikipedia article about the ninth author.	Page name	dewisol
Coauthor	coauthor	Coauthor	Llinyn	anghymeradwyedig
Coauthors	coauthors	Coauthors	Llinyn	anghymeradwyedig
Editor last name 2	editor2-last editor2	The surname of the second editor; don't wikilink, use 'editor2-link'.	Llinell	dewisol
Editor first name 2	editor2-first editor2-given	Given or first name, middle names, or initials of the second editor; don't wikilink.	Llinell	dewisol
Editor last name 3	editor3-last editor3	The surname of the third editor; don't wikilink, use 'editor3-link'.	Llinell	dewisol
Editor first name 3	editor3-first editor3-given	Given or first name, middle names, or initials of the third editor; don't wikilink.	Llinell	dewisol
Editor last name 4	editor4-last editor4	The surname of the fourth editor; don't wikilink, use 'editor4-link'.	Llinell	dewisol
Editor first name 4	editor4-first editor4-given	Given or first name, middle names, or initials of the fourth editor; don't wikilink.	Llinell	dewisol
Editor last name 5	editor5-last editor5	The surname of the fifth editor; don't wikilink, use 'editor5-link'.	Llinell	dewisol
Editor first name 5	editor5-first editor5-given	Given or first name, middle names, or initials of the fifth editor; don't wikilink.	Llinell	dewisol
Editor last name 6	editor6-last editor6	The surname of the sixth editor; don't wikilink, use 'editor6-link'.	Llinell	dewisol
Editor first name 6	editor6-first editor6-given	Given or first name, middle names, or initials of the sixth editor; don't wikilink.	Llinell	dewisol
Editor last name 7	editor7-last editor7	The surname of the seventh editor; don't wikilink, use 'editor7-link'.	Llinell	dewisol
Editor first name 7	editor7-first editor7-given	Given or first name, middle names, or initials of the seventh editor; don't wikilink.	Llinell	dewisol
Editor last name 8	editor8-last editor8	The surname of the eighth editor; don't wikilink, use 'editor8-link'.	Llinell	dewisol
Editor first name 8	editor8-first editor8-given	Given or first name, middle names, or initials of the eighth editor; don't wikilink.	Llinell	dewisol
Editor last name 9	editor9-last editor9	The surname of the ninth editor; don't wikilink, use 'editor9-link'.	Llinell	dewisol
Editor first name 9	editor9-first editor9-given	Given or first name, middle names, or initials of the ninth editor; don't wikilink.	Llinell	dewisol
editor-link	editor-link	dim disgrifiad	Llinyn	dewisol
editor1-link	editor1-link	dim disgrifiad	Llinyn	dewisol
editor2-link	editor2-link	dim disgrifiad	Llinyn	dewisol
editor3-link	editor3-link	dim disgrifiad	Llinyn	dewisol
editor4-link	editor4-link	dim disgrifiad	Llinyn	dewisol
Translator last name	translator-last translator translator-last1 translator1 translator1-last	The surname of the translator; don't wikilink, use 'translator-link'; can suffix with a numeral to add additional translators.	Llinyn	dewisol
Translator first name	translator-first translator1-first translator-first1	Given or first name, middle names, or initials of the translator; don't wikilink, use 'translator-link'; can suffix with a numeral to add additional translators.	Llinyn	dewisol
Translator link	translator-link translator-link1 translator1-link	Title of existing Wikipedia article about the translator; can suffix with a numeral to add additional translators.	Page name	dewisol
Translator last name 2	translator-last2 translator2 translator2-last	The surname of the second translator; don't wikilink, use 'translator-link'.	Llinyn	dewisol
Translator first name 2	translator-first2 translator2-first	Given or first name, middle names, or initials of the second translator; don't wikilink, use 'translator-link'.	Llinyn	dewisol
Translator last name 3	translator-last3 translator3 translator3-last	The surname of the third translator; don't wikilink, use 'translator-link'.	Llinyn	dewisol
Translator first name 3	translator-first3 translator3-first	Given or first name, middle names, or initials of the third translator; don't wikilink, use 'translator-link'.	Llinyn	dewisol
Translator last name 4	translator-last4 translator4 translator4-last	The surname of the fourth translator; don't wikilink, use 'translator-link'.	Llinyn	dewisol
Translator first name 4	translator-first4 translator4-first	Given or first name, middle names, or initials of the fourth translator; don't wikilink, use 'translator-link'.	Llinyn	dewisol
Translator last name 5	translator-last5 translator5 translator5-last	The surname of the fifth translator; don't wikilink, use 'translator-link'.	Llinyn	dewisol
Translator first name 5	translator-first5 translator5-first	Given or first name, middle names, or initials of the fifth translator; don't wikilink, use 'translator-link'.	Llinyn	dewisol
Translator last name 6	translator-last6 translator6 translator6-last	The surname of the sixth translator; don't wikilink, use 'translator-link'.	Llinyn	dewisol
Translator first name 6	translator-first6 translator6-first	Given or first name, middle names, or initials of the sixth translator; don't wikilink, use 'translator-link'.	Llinyn	dewisol
Translator last name 7	translator-last7 translator7 translator7-last	The surname of the seventh translator; don't wikilink, use 'translator-link'.	Llinyn	dewisol
Translator first name 7	translator-first7 translator7-first	Given or first name, middle names, or initials of the seventh translator; don't wikilink, use 'translator-link'.	Llinyn	dewisol
Translator last name 8	translator-last8 translator8 translator8-last	The surname of the eighth translator; don't wikilink, use 'translator-link'.	Llinyn	dewisol
Translator first name 8	translator-first8 translator8-first	Given or first name, middle names, or initials of the eighth translator; don't wikilink, use 'translator-link'.	Llinyn	dewisol
Translator last name 9	translator-last9 translator9 translator9-last	The surname of the ninth translator; don't wikilink, use 'translator-link'.	Llinyn	dewisol
Translator first name 9	translator-first9 translator9-first	Given or first name, middle names, or initials of the ninth translator; don't wikilink, use 'translator-link'.	Llinyn	dewisol
Translator link 2	translator-link2 translator2-link	Title of existing Wikipedia article about the second translator.	Page name	dewisol
Translator link 3	translator-link3 translator3-link	Title of existing Wikipedia article about the third translator.	Page name	dewisol
Translator link 4	translator-link4 translator4-link	Title of existing Wikipedia article about the fourth translator.	Page name	dewisol
Translator link 5	translator-link5 translator5-link	Title of existing Wikipedia article about the fifth translator.	Page name	dewisol
Translator link 6	translator-link6 translator6-link	Title of existing Wikipedia article about the sixth translator.	Page name	dewisol
Translator link 7	translator-link7 translator7-link	Title of existing Wikipedia article about the seventh translator.	Page name	dewisol
Translator link 8	translator-link8 translator8-link	Title of existing Wikipedia article about the eighth translator.	Page name	dewisol
Translator link 9	translator-link9 translator9-link	Title of existing Wikipedia article about the ninth translator.	Page name	dewisol
Country Code	country-code	Two-letter abbreviation of the country issuing the patent.	Anhysbys	dewisol

COinS

This template produces COinS metadata; see COinS in Wikipedia for background information.

Additional parameters

author-mask — This parameter is primarily intended for use in bibliographies where multiple works by a single author are listed; it is not for use in in-text citations, as it presents the same problems as the use of ibid (see WP:IBID). It replaces the name of the first author (which must still be provided to garner metadata) with a strike-through dash (—) author-mask em in length. So, if |author-mask=1 then the dash will be one em in length, if |author-mask=2 it will be two em long, and so on. Set author-mask to a text value to display a word instead – for example, "with". You must still include |last= and |first= for metadata purposes.