Template:Citation Style documentation/id2

These identifiers create links and are designed to accept a single value. Using multiple values or other text will break the link and/or invalidate the identifier. In general, the parameters should include only the variable part of the identifier, e.g.  or.

When an URL is equivalent to the link produced by the corresponding identifier (such as a DOI), don't add it to any URL parameter but use the appropriate identifier parameter, which is more stable and may allow to specify the access status. The url parameter or title link can then be used for its prime purpose of providing a convenience link to a free-to-read copy of the source that would not otherwise be obviously accessible.


 * : arXiv identifier; for example:  (before April 2007) or   (April 2007 – December 2014) or   (since January 2015). Do not include extraneous file extensions like ".pdf" or ".html".  Aliases:.
 * : Amazon Standard Identification Number; if first character of value is a digit, use . Because this link favours one specific distributor, include it only if standard identifiers are not available. Example  .  Aliases:.
 * : ASIN top-level domain for Amazon sites other than the US; valid values:,  ,  ,  ,  ,  ,  ,  ,  ,  ,  .  Aliases:.
 * : bibcode; used by a number of astronomical data systems; for example: .  Aliases:.
 * : bioRxiv id, a 6-digit number at the end of the biorXiv URL (e.g.  for http://biorxiv.org/content/early/2016/10/01/078733 or https://dx.doi.org/10.1101/078733).  Aliases:.
 * : CiteSeerX id, a string of digits and dots found in a CiteSeerX URL (e.g.  for http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.176.341).  Aliases:.
 * : Digital object identifier; for example: . It is checked to ensure it begins with (10.).  Aliases:.
 * : Date the DOI was found to be non-working at https://dx.doi.org. Use the same format as other dates in the article. Aliases:.
 * : International Standard Serial Number for the electronic media of a serial publication; eight characters may be split into two groups of four using a hyphen, but not an en dash or a space; example .  Aliases:.
 * : Handle System identifier for digital objects and other resources on the Internet; example .  Aliases:.
 * : International Standard Book Number; for example: .  Hyphens in the ISBN are optional, but preferred. Use the ISBN actually printed on or in the book. Use the 13-digit ISBN – beginning with 978 or 979 – when it is available. If only a 10-digit ISBN is printed on or in the book, use it. ISBNs can be found on the page with the publisher's information – usually the back of the title page – or beneath the barcode as a number beginning with 978 or 979 (barcodes beginning with any other numbers are not ISBNs). For sources with the older 9-digit SBN system, use . Do not convert a 10-digit ISBN to 13-digit by just adding the 978 prefix; the last digit is a calculated check digit and just making changes to the numbers will make the ISBN invalid. This parameter should hold only the ISBN without  additional characters. It is checked for length, invalid characters – anything other than numbers, spaces, and hyphens, with "X" permitted as the last character in a 10-digit ISBN – and the proper check digit.  Aliases:.
 * : In very rare cases, actually used ISBNs (as printed on books) do not follow the standard checksum algorithm. In order to suppress the error message, the true parameter can be used to disable the checksum check in these cases. If the problem is down to a mere typographical error in a third-party source, correct the ISBN instead of overriding the error message. Aliases:.
 * : International Standard Music Number; for example: . Hyphens or spaces in the ISMN are optional. Use the ISMN actually printed on or in the work. This parameter should hold only the ISMN without any additional characters. It is checked for length, invalid characters – anything other than numbers, spaces, and hyphens – and the proper check digit.  Aliases:.
 * : International Standard Serial Number; eight characters may be split into two groups of four using a hyphen, but not an en dash or a space; example .  Aliases:.
 * : Jahrbuch über die Fortschritte der Mathematik; example .  Aliases:.
 * : JSTOR reference number; for example: .  Aliases:.
 * : Library of Congress Control Number. When present, alphabetic prefix characters are to be lower case; example .  Aliases:.
 * : Mathematical Reviews; example .  Aliases:.
 * : OCLC; WorldCat's Online Computer Library Center; example .  Aliases:.
 * : Open Library identifier; do not include "OL" in the value; example .  Aliases:.
 * : Office of Scientific and Technical Information; example .  Aliases:.
 * : PubMed Central; use article number for open repository full-text of a journal article, e.g. . Do not include "PMC" in the value. .  Aliases:.
 * : Date that goes live; if this date is in the future, then  is not linked until that date.  Aliases:.
 * : PubMed; use unique identifier; example    Aliases:.
 * : Request for Comments; example .  Aliases:.
 * : Standard Book Number; example .  Aliases:.
 * : Social Science Research Network; example .  Aliases:.
 * : Semantic Scholar corpus ID; example .  Aliases:.
 * : Zentralblatt MATH; example  For zbMATH search results like   use  .  Aliases:.