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. rfc=822 or pmc=345678.

  • arxiv: arXiv identifier; for example: arxiv=hep-th/9205027 (before April 2007) or arxiv=0706.0001 or arxiv=1501.00001 (since April 2007). Do not include extraneous file extensions like ".pdf" or ".html".
  • asin: Amazon Standard Identification Number; if first character of asin value is a digit, use isbn.
    • asin-tld: ASIN top-level domain for Amazon sites other than the US; valid values: au, br, ca, cn, co.jp, co.uk, de, es, fr, it, mx
  • bibcode: Bibcode; used by a number of astronomical data systems; for example: 1974AJ.....79..819H
  • doi: Digital object identifier; for example: 10.1038/news070508-7. It is checked to ensure it begins with (10.).
    • doi-broken-date: Date the DOI was found to be non-working at http://dx.doi.org. Use the same format as other dates in the article. Alias: doi_brokendate, doi-inactive-date
  • eissn: 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. Alias: EISSN
  • hdl: Handle System identifier for digital objects and other resources on the Internet. Alias: HDL
  • isbn: International Standard Book Number; for example: 978-0-8126-9593-9.
  • ismn: International Standard Music Number; for example: 979-0-9016791-7-7. 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. Alias: ISMN
  • issn: 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. Alias: ISSN
  • jfm: Jahrbuch über die Fortschritte der Mathematik
  • jstor: JSTOR reference number; for example: jstor=3793107 will generate JSTOR 3793107.
  • lccn: Library of Congress Control Number. When present, alphabetic prefix characters are to be lower case.
  • mr: Mathematical Reviews
  • oclc: OCLC; WorldCat's Online Computer Library Center
  • ol: Open Library identifier; do not include "OL" in the value.
  • osti: Office of Scientific and Technical Information
  • pmc: PubMed Central; use article number for full-text free repository of a journal article, e.g. pmc=345678. Do not include "PMC" in the value.
  • pmid: PubMed; use unique identifier.
  • rfc: Request for Comments
  • ssrn: Social Science Research Network
  • zbl: Zentralblatt MATH