Fontem paginae Formula:Citation/doc inspicere

{{Documentation subpage}}
{{Formula obsoleta|Opus}}
<!-- EDIT TEMPLATE DOCUMENTATION BELOW THIS LINE -->

{{For2|the <sup>''&#91;citation needed&#93;''</sup> template|{{tl|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 {{Tl|Cite book}} and {{Tl|Cite web}}. The default behavior sometimes differs from that of the Cite templates; for example, this template by default generates anchors for [[Harvard reference]]s 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.

<code><nowiki>{{Citation |last= |first= |year= |title= |publisher= |publication-place= |page= |url= |accessdate= }}</nowiki></code>

{| class="wikitable"
|-
| <pre>{{Citation
| last =
| first =
| year =
| title =
| publisher =
| publication-place =
| page =
| url =
| accessdate =
}}</pre>
|}
* '''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 {{para|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 [[Uniform resource locator|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<ref group = "n" name = "dates" /> when the url was accessed.

===Example===
{| class="wikitable"
|-
| <pre>{{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}}
}}
</pre>
| {{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}}
}}
|}

==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&nbsp;— these may be mutually exclusive where indicated. Some hyphenated names can also be placed without hyphens.

{| class="wikitable"
|-
| <pre>{{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 =
}}
</pre>
|}

==Parameters==
===Syntax===
{{csdoc|syntax}}

{{csdoc|coins}}

{{csdoc|sep_comma}}

===Description===
====Authors====
{{csdoc|author}}
{{csdoc|coauthors}}
{{csdoc|others}}
====Editors====
{{csdoc|editor}}
====Title====
{{csdoc|title_italics}}
{{csdoc|chapter}}
{{csdoc|type}}
====Language====
{{csdoc|language}}
====Date====
{{csdoc|date}}
====Periodical====
{{csdoc|journal}}
====Publisher====
{{csdoc|publisher}}
====Series====
{{csdoc|series}}
====Edition====
{{csdoc|edition}}
====Volume====
{{csdoc|volume}}
====In-source locations====
{{csdoc|pages}}
====Identifiers====
{{anchor|id1}}{{csdoc|id1}}
{{anchor|id2}}{{csdoc|id2}}
====URL====
{{anchor|url}}{{csdoc|url}}
====Laysummary====
{{csdoc|lay}}
====Display options====
{{csdoc|display|cs2=y}}
:* '''postscript''': Set terminal punctuation. Omit or leave blank to remove the trailing full stop (period). 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 {{para|quote}} is specified, when {{para|postscript|.}} is forced.
====Ref====
{{csdoc|ref}}

==Examples==
===Books===
{| class="wikitable"
|-
| Three authors, a volume, and an edition. Ampersand (&amp;) forced before final author's name.
| <pre>{{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
}}
</pre>
| {{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
}}
|}

===Web===
{| class="wikitable"
|-
| Web page
| <pre>{{Citation
| url = http://nrhp.focus.nps.gov
| title = NPS Focus
| work = National Register of Historic Places
| publisher = [[National Park Service]]
| accessdate = November 30, 2010
}}
</pre>
| {{Citation
| url = http://nrhp.focus.nps.gov
| title = NPS Focus
| work = National Register of Historic Places
| publisher = [[National Park Service]]
| accessdate = November 30, 2010
}}
|-
| Archived page
| <pre>{{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
}}
</pre>
| {{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}}
|}

===Journals, newspapers, magazines, or other periodicals===
{| class="wikitable"
|-
| Journal article
| <pre>{{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
}}
</pre>
| {{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
}}
|-
| Journal article with multiple authors and identifier
| <pre>{{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
}}
</pre>
| {{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
}}
|-
| Newspaper article
| <pre>{{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
}}
</pre>
| {{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
}}
|-
| Conference paper
| <pre>{{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
}}
</pre>
| {{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}}
|}

===Parts of books, including encyclopedia articles===
{| class="wikitable"
|-
|Manuscript published in an edited compilation
|<pre>{{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
}}
</pre>
| {{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
}}
|-
| Work with an editor but no author
| <pre>{{Citation
| editor-last = Vogel
| editor-first = Dan
| title = Early Mormon Documents
| volume = 1
| publisher = Signature Books
| publication-date = 1996
| isbn = 1–56085–072–8
}}
</pre>
| {{Citation
| editor-last = Vogel
| editor-first = Dan
| title = Early Mormon Documents
| volume = 1
| publisher = Signature Books
| publication-date = 1996
| isbn = 1–56085–072–8
}}
|-
| Encyclopedia article by a named author
| <pre>{{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
}}
</pre>
| {{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
}}
|-
| Encyclopedia article with no named author
| <pre>{{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
}}
</pre>
| {{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
}}
|}

===Republications, or edited quotations in a periodical article===
{| class="wikitable"
|-
| Manuscript edited and published in a journal
| <pre>{{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
}}</pre>
| {{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
}}
|-
| Manuscript written at one date and place, then published in a periodical at a different date and place with commentary by the editor.
| <pre>{{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
}}
</pre>
| {{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
}}
|}

===Press release===
{| class="wikitable"
|-
| Press release with quotation
| <pre>{{Citation
| 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}}
</pre>
| {{Citation
| 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}}
|}

==Citing patents==
===Parameters (all are optional)===
{| class="wikitable"
|-
| <pre>{{Citation
| inventor-last =
| inventor-first =
| inventorlink =
| inventor2-last =
| inventor2-first =
| inventorlink2 =
| publication-date =
| issue-date =
| title =
| country-code =
| description =
| patent-number =
}}</pre>
|
* '''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 "<code>&amp;#91;</code>" for "[" and "<code>&amp;#93;</code>" for "]"
* '''country-code''': [[ISO 3166-1 alpha-2|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===
{| class="wikitable"
| United States patent with multiple inventors
| <pre>{{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}}
</pre>
| {{Citation
| inventor1-first = Mikael | inventor1-last = Degermark
| inventor2-first = Andrej | inventor2-last = Brodnik
| inventor3-first = Svante | inventor3-last = Carlsson
| inventor4-first = Stephen | inventor4-last = Pink
| 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}}
|}

==Anchored citations==
This template can generate a citation that can be combined with [[WP:CITESHORT|shortened footnotes]] or [[Wikipedia:Parenthetical referencing|parenthetical referencing]]. It does this by creating an [[HTML element#Anchor|HTML anchor]] containing an ID. The special parameter {{para|ref|harv}} generates an ID suitable for [[Harvard referencing]] templates such as {{tl|harv}} as specified in the next section; this is the default for the {{tl|citation}} template. If an empty {{para|ref}} is given, no anchor is generated; this is the default for the Cite templates such as {{tl|cite book}} and {{tl|cite news}}. You can also specify the ID directly, using the {{para|ref|<var>ID</var>}} parameter. For example, suppose an article's ''References'' section contains the markup:
* <code><nowiki>{{Citation |author=Sigmund Freud |title=Civilization and Its Discontents |year=1930 |ref=CivDis}}</nowiki></code>
which generates the citation:
* {{Citation |author=Sigmund Freud |title=Civilization and Its Discontents |year=1930 |ref=CivDis}}
Then, the markup "<code><nowiki>([[#CivDis|Freud 1930]])</nowiki></code>" generates a parenthetical reference "([[#CivDis|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 {{tl|harv}} are computed from the last names of the authors and the year of the cited source. For example, the markup "<code><nowiki>{{harv|Wright|Evans|1851|p=ix}}</nowiki></code>" generates the Harvard reference "{{harv|Wright|Evans|1851|p=ix}}", which wikilinks to the citation whose markup and appearance are shown below:
* <code><nowiki>{{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}}</nowiki></code>
* {{ec
	| id = Wright et al (1851)
	| c = {{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
	}}
}}

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

Related methods which leave only a number in the text are to use the {{tl|harvnb}} template enclosed in the <nowiki><ref></ref></nowiki> html code, or to use the {{tl|qc}} and {{tl|ec}} templates. The example above would become <syntaxhighlight lang="wikitext" inline>{{ec|id=Wright et al (1851)|c={{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}}}}</syntaxhighlight>, while the footnote would be generated by <syntaxhighlight lang="wikitext" inline><ref>{{qc|id=Wright et al (1851)}}</ref></syntaxhighlight>, and will look as follows:

:17. {{qc|id=Wright et al (1851)}}

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 [[#Citing patents|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 {{para|last1}} (or {{para|last}}), {{para|last2}}, {{para|last3}}, and {{para|last4}}, and similarly for {{para|editor1-last}} etc. and for {{para|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 "<code><nowiki>{{Citation | author = Sigmund Freud | title = The Ego and the Id | year = 1923}}</nowiki></code>" no last name is given, so this citation cannot be combined with the Harvard reference "<code><nowiki>{{harv|Freud|1923}}</nowiki></code>". To make these {{tl|citation}} and {{tl|harv}} invocations compatible, either replace "{{para|author|Sigmund Freud}}" with "{{para|first|Sigmund}} {{para|last|Freud}}", or add "{{para|ref|<nowiki>{{harvid|Freud|1923}}</nowiki>}}" to the {{tl|citation}} invocation, or add the same ref parameter (say, "{{para|ref|EgoId}}") to both the {{tl|citation}} and the {{tl|harv}} invocations.

Similarly, the year is used, as specified by {{para|year}}. If no year is given, this template attempts to derive the year from {{para|date}} (or, if no date is given, from {{para|publication-date}}) by applying the [[mw:Help:Extension:ParserFunctions##time|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 {{para|year}}. Note that if only a year, say 2005, is known you must use {{para|year|2005}} rather than {{para|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 {{tl|harv}}-compatible IDs:
* {{Citation |last1=Montes |first1=G. |last2=Halterman |first2=J. S. |year=2008a |journal=Pediatrics |volume=121 |issue=4 |pages=e821–6 |title=Association of Childhood Autism Spectrum Disorders and Loss of Family Income |doi=10.1542/peds.2007-1594 |pmid=18381511 |url= http://pediatrics.aappublications.org/cgi/content/full/121/4/e821 }}
* {{Citation |last1=Montes |first1=G. |last2=Halterman |first2=J. S. |year=2008b |journal=Pediatrics |volume=122 |issue=1 |pages=e202–8 |title=Child Care Problems and Employment Among Families with Preschool-aged Children with Autism in the United States |doi=10.1542/peds.2007-3037 |pmid=18595965 |url= 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 "<code>CITEREFMontesHalterman2008</code>". To avoid this problem, distinguish the citations by appending suffixes to the years, ''e.g.'', "{{para|year|2008a}}" and "{{para|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|External links]]''.

==Dates==
<references group="n"><ref name="dates" group="n">
* The format of dates in the references of an article should use a consistent and unambiguous style. Example formats used in Wikipedia citations include:
:*''2009''
:*''2009-09-14'' (ISO standard format: YYYY-MM-DD)
:*''14 September 2009''
:*''September 14, 2009'' (with comma)
:*''2009 Sep 14''
:*''September 2009''
:*''Sept./Oct. 2009''
* As indicated above, month names are sometimes abbreviated, ''e.g.'', September to "Sept" or "Sept." or "Sep" or "Sep."
* Dates should not be linked in references.
* Please see ''[[Wikipedia:Manual of Style (dates and numbers)#Dates]]'' for more guidance about formatting dates.
</ref>
</references>

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

==COinS==
{{UF-COinS}}

=={{Visible anchor|Additional parameters}}==
{{AuthorMask doc}}

<includeonly>
[[Categoria:Formulae citationis]]
</includeonly>