Template:Citation Style documentation/registration

Citations of online sources that require registration or a subscription are acceptable in Wikipedia as documented in Verifiability § Access to sources. As a courtesy to readers and other editors, editors should signal the access restrictions of the external links included in a citation. Nota bene: access icons do not display correctly for editors who use Modern skin.

Four access levels can be used:

As there are often multiple external links with different access levels in the same citation, these values are attributed to a particular external link.

Access indicators for url-holding parameters[edit]

Sources linked by |url=, |article-url=, |chapter-url=, |contribution-url=, |entry-url=, |map-url=, and |section-url= are presumed to be free-to-read.[1] When they are not free-to-read, editors should mark those sources with the matching access-indicator parameter so that an appropriate icon is included in the rendered citation. Because the sources linked by these url-holding parameters are presumed to be free-to-read, they may not be marked as free.

url-holding and access-indicator parameters
url access allowed keywords
url= url-access= registration Free registration required
limited Free access subject to limited trial, subscription normally required
subscription Paid subscription required
article-url= article-url-access=
chapter-url= chapter-url-access=
contribution-url= contribution-url-access=
entry-url= entry-url-access=
map-url= map-url-access=
section-url= section-url-access=
Access indicator for named identifiers[edit]

Links inserted by named identifiers are presumed to lie behind a paywall or registration barrier – exceptions listed below. When they are free-to-read, editors should mark those sources with the matching access-indicator parameter so that an appropriate icon is included in the rendered citation. Because the sources linked by these named-identifier parameters are not presumed to be free-to-read, they may not be marked as limited, registration, or subscription.

named-identifier and access-indicator parameters
identifier access allowed keywords
bibcode= bibcode-access= free Freely accessible
doi= doi-access=
hdl= hdl-access=
jstor= jstor-access=
ol= ol-access=
osti= osti-access=
s2cid= s2cid-access=

Some named-identifiers are always free-to-read. For those named-identifiers there are no access-indicator parameters, the access level is automatically indicated by the template. These named identifiers are:

  • |arxiv=
  • |biorxiv=
  • |citeseerx=
  • |pmc=
  • |rfc=
  • |ssrn=
  1. This guidance does not restrict linking to websites that are being used as sources to provide content in articles.