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 can signal the access restrictions of the external links included in a citation.

Four access levels can be used:

• free: the source is free to read for anyone (this applies in particular to articles in open access)
• registration: a free registration is required to access the source
• limited: there are other constraints (such as a cap on daily views) to freely access this source
• subscription: the source is only accessible via a paid subscription ("paywall")

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 level of |url=

Links inserted with |url= are expected to be free to read by default. If not, editors can use one of

• |url-access=subscription
• |url-access=registration
• |url-access=limited

to indicate the relevant access restriction.

Access level of identifiers

Links inserted by identifiers such as |doi= are not expected to offer a free full text by default. If they do, editors can use |doi-access=free (in the case of |doi=) to indicate the relevant access level. The following identifiers are supported:

• |bibcode= with |bibcode-access=free
• |doi= with |doi-access=free
• |hdl= with |hdl-access=free
• |jstor= with |jstor-access=free
• |ol= with |ol-access=free
• |osti= with |osti-access=free

Some identifiers always link to free full texts. In this case, the access level is automatically indicated by the template. This is the case for |arxiv=, |biorxiv=, |citeseerx=, |pmc=, |rfc= and |ssrn=.

Ambiguous access parameters

The parameters |registration=yes and |subscription=yes can also be used to indicate the access level of a citation. However, they do not indicate which link they apply to, so editors are encouraged to use |url-access=registration and |url-access=subscription instead, when the restriction applies to |url=. If the restriction applies to an identifier, these parameters should be omitted.

These parameters add a link note to the end of the citation:

• registration: For online sources that require registration, set |registration=yes (or y, or true); superseded by subscription if both are set.
• subscription: For online sources that require a subscription, set |subscription=yes (or y, or true); supersedes registration if both are set.

Setting |registration= or |subscription= to any value other than y, yes, or true will generate an error message.