Metadata Input Guidelines: Identifier

Element Name



A numeric or alphanumeric string or a URL that identifies the item in a particular context.

Where Can the Identifier Information be Found?

Item Types Information Sources
For text
  • a title page
  • a documentation page
  • the cover of a report or book
For webpages or online resources
  • a website
For any item type
  • a library catalog record
  • an OCLC record
  • local accession records
  • the physical item
  • accompanying or supplementary material

How Identifier Works in the Metadata Form

1. Identifier qualifier – drop-down menu
2. Identifier – text field
Yes - to include multiple identifiers, click ‘Add’ to repeat all field parts
No (more information)

How Should the Identifier be Filled in?

Guideline Example
  • Enter the identifier exactly as it is found in the item or record
M1500.G68 A4
  • Include one or more relevant identifiers when they are available
  • Include additional identifiers if they aid information-gathering


Z232.A56 J67 1853z
  • For Local Control Numbers include the Institution code followed by an underscore ( _ ) before the number
  • Local practice (within UNT Digital Projects) is to change some punctuation of Local Control Numbers when they are used as filenames during scanning (for example, '.' becomes '-'); generally, the identifier is entered using file-name punctuation rather than the original punctuation

Original: 76-085.071
Local-Cont-No: PBPM_76-085-071
LCCN - Library of Congress Control Number

OTHER - Other

Other Examples

Book: The Forgotten Colony: San Patricio de Hibernia: The History, the People and the Legends of the Irish Colony of McMullen-McGloin
CALL-NO: F392.S237 H43 1981
UNTCAT: b2047410
ISBN: 0890152934
ISBN: 9780890152935
LCCN: 88-103244
OCLC: 18258092
Journal issue: Chemical Literature, Volume 27, Number 1, Spring 1975
ISSN: 0364-1929
OCLC: 1553979
Department of Agriculture pamphlet: Production of pumpkins and squashes.
SUDOC: A 1.35:141
OCLC: 68565990
UNTCAT: b3064507
Architectural Drawing: Birdseye Perspective from Northwest, Restoration Legation de France, Austin, Texas, For Daughters of the Republic of Texas
Music score: Ballet du Temple de la paix
CALL-NO: M1520.L87 B3
OCLC: 23032723
RISM: RISM A/I, L 3049
UNTCAT: b1373221
Congressional report: Merit Pay for Elementary and Secondary School Teachers: Background Discussion and Analysis of Issues
CRS: 83-541S
LOCAL-CONT-NO: 83-541S 1983-09-14
Map: Location and Depths of the Artesian Wells of the Black and Grand Prairies of Texas
OCLC: 25650057
Office of Technology Assessment report: Informing the Nation: Federal Information Dissemination in an Electronic Age
SUDOC: Y 3.T 22/2:2 In 3/9/sum.
OCLC: 18605251


Glossary of Identifier Types

Type Code Definition
Archival Resource Key ARK A persistent, unique number systematically assigned to an item for archival purposes
BRAC Number BRAC-NUM A document identification number assigned to items held by the Base Reassignment and Closure Commission (BRAC)
Call Number CALL-NO An alphanumeric code assigned to each item in a library to classify and indicate its location on the shelves
Center for AeroSpace Information Number CASI A document identification number assigned to items held by the Center For AeroSpace Information (including NASA/NACA technical reports)
CRS Report Number CRS A number assigned to Congressional Research Service reports
Digital Object Identifier DOI The string used as an identifier by the DOI System for an intellectual property entity
Government Document Number GOVNO Designates documents published by government agencies, excluding SuDoc and TxDoc numbers
Grant Number GRANTNO A number assigned to a grant by the granting agency
International Standard Book Number ISBN A unique machine-readable identification number for books

International Standard Book Numbers (ISBNs) are defined in ISO Standard 2108.
International Standard Serial Number ISSN An eight-digit number which identifies periodical publications, including electronic serials
Library of Congress Control Number LCCN Coded numbers assigned by the Library of Congress to individual items
Accession or Local Control Number LOCAL-CONT-NO Accession numbers assigned by a museum, archive, or special collection, or local numbers used by a collector to identify elements of a personal collection
OCLC Accession Number OCLC The unique identification number listed in the Online Computer Library Center (OCLC) WorldCat record as part of their worldwide cataloging and interlibrary loan database
Office of Scientific & Technical Information Report Number OSTI A document identification number assigned to items published or held by the U.S. Office of Science & Technology Information
Patent Number PAT-NO A number assigned to a patent application by the patent office
Report Number REP-NO A publisher-supplied number identifying a report, usually within a series of similar reports

A report number may be a standard technical report number formulated to the ANSI/NISO Z39.23 standard, or a less standardized number designed to work within an organizational scheme of the issuing agency's publications.
RISM Number RISM A unique identifier within Répertoire International des Sources Musicales (RISM), the International Inventory of Musical Sources
Series Number SERIESNO A number associated to a publication that is part of a series or serial, but is not a "Report"
SuDoc Number SUDOC Superintendent of Documents Classification (SuDoc) numbers are assigned to federal documents to group government publications by authoring agencies
TxDoc Number TXDOC Texas Document Classification (TxDoc) numbers are assigned to Texas state documents as unique identifiers for publications of the state government
UNT Catalog Number UNTCAT The bibliographic record number for a specific UNT library record
Uniform Resource Locator URL The global address of the document or resource on the World Wide Web
Uniform Resource Name URN A persistent resource identifier (including PURLs)
Universally Unique Identifier UUID An identifier used in software construction
Other Identifier OTHER Used for identifiers that do not fit into another category
  • Identifiers provide information needed to retrieve a file from the storage system, to access a bitstream within a file, or to locate a physical object.


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