Template:Cite linked authority file/doc

The purpose of this template is to provide a standardised citation for information (e.g., date of birth) sourced from Library of Congress (LoC) Authorities data files, which can conveniently be accessed through the OCLC-WorldCat Identities database. The template will generate the citation and an external link to the corresponding Linked Authority File (LAF) in the WorldCat Identities database, from where the information was sourced.

Usage
All field names must be lowercase.

Fields
The available fields are:
 * id: required parameter. This is the unique identifier of the LAF record, for example: n79-21425 is for Johann Sebastian Bach.
 * text: optional parameter. If specified, used for free text to describe the kind of information that has been sourced, for example: Date and other names. If not specified, the text defaults to "Date".
 * accessdate: optional parameter. Full date when item is accessed, in ISO 8601 YYYY-MM-DD format, for example: 2024-July-. (Must not be wikilinked.)

Purpose
The Library of Congress (LOC) Authorities is a database consisting of individual authority records, i.e. identifying records for entities, such as authors or organizations, contained within the LOC cataloging system of the library's more than 12 million works. To quote from the LOC website, an authority record is: ...a tool used by librarians to establish forms of names (for persons, places, meetings, and organizations), titles, and subjects used on bibliographic records. Authority records enable librarians to provide uniform access to materials in library catalogs and to provide clear identification of authors and subject headings. These records, available online free-of-charge and typically in MARC 21 format, contain a variety of identifying and annotative remarks on these entities &mdash; such as alternative or full names of people and organisations, date or year of birth of authors of books or subjects of books, cross-referencing of affiliated entities, and so on.

The information contained in these records can frequently be a useful source for base information, such as exact date of birth or variant names and titles, that may be difficult to verify or obtain from other generally available sources. It can also be a useful resource for distinguishing between similarly named (but distinct) individuals, or cross-referencing individuals whose names are variably spelled/written.

While the LOC Authorities database can be accessed and searched directly through its website (https://authorities.loc.gov/), the interface is reasonably complex and the search result URLs often resolve to something quite lengthy.

An easier, more intuitive interface, compared to the LOC Authorities data, is provided by OCLC-WorldCat, in their database. This is an open-access online database and cataloging index compiled from the 10,000+ member libraries worldwide, interlinked with the Library of Congress, and other major cataloging systems, such as Deutsche Bibliothek (DNB).

The WorldCat Identities database collates a range of information on the "identities" (authors, organisations, subjects, etc.) associated with publications and other materials held in many of the world's libraries. An Identity record will very often (but not always) have one or more Linked Authority Files (LAF) associated with it, which are essentially drawn from the LOC Authorities record associated with that identity/entity/author.

How-to
One common usage of Linked Authority Files would be to ascertain birth date information (or year, if not the exact date) for an individual author, or subject of a published work. Finding alternative, former, or variant names is another possibility.

Just about any person or institution who has ever written or been associated with a book or other published material will have an Identities record; and a large majority will also have a LAF record. The LAF record quite often will contain some identifying or annotated information concerning the individual, such as date of birth (or death) data. Not all records by any means have this, but most do.

Note, there is a systemic bias of sorts in favour of English-language published identities, and publications in Latin orthographical scripts, tending all the more so for the LAF records.

Steps to accomplish this:
 * 1) Go to the Worldcat Identities main page: https://www.worldcat.org/identities/
 * 2) Enter the name (format: Lastname, Firstname ) of the individual in the searchbox (e.g. Le Guin, Ursula)
 * 3) Select the desired entry from the list of identities that will be generated – usually, it will be the topmost-entry. Hint: sometimes there will be a couple of entries for the identity, usually select, if available, an entry marked with the "Controlled Personal Identity" icon (for individuals), or the "Controlled Corporate Identity" icon (for organisations), as these will have an associated LAF record. (e.g., select Le Guin, Ursula K. 1929-2018 (Fiction) in this example.)
 * 4) This brings up the Identities file. Scroll down to the "Useful Links" section. Typically, you will see a "Library of Congress Authority File (English)" link.
 * 5) Clicking on the link will bring up the LCNAF record page, which displays the various (and variable) fields of the Authorities record. The birth date (or death date) information, if present, will normally appear in one of the fields below. Other useful information may also be cited in the article.
 * 6) To use this as a cited source for the DOB, take the "Identifier" number shown (in this example, n78-95474) and apply it to the template, as follows:

BLP reminder
When sourcing information regarding living persons, please be mindful of the privacy sections in the WP:BLP policy (especially WP:DOB and WP:BLPPRIMARY). It may be appropriate, for example, to omit the full date of birth of a living person in an article, even if the LOC Authorities file contains this information; and instead use just the year of birth. The addition of information into articles sourced via this method should comply generally with all other relevant policies, just as for any other sourcing method.