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Introduction


MARC 21 Authority
October 2009

The five MARC 21 communication formats, MARC 21 Format for Bibliographic Data, MARC 21 Format for Authority Data, MARC 21 Format for Holdings Data, MARC 21 Format for Classification Data, and MARC 21 Format for Community Information, are widely used standards for the representation and exchange of bibliographic, authority, holdings, classification, and community information data in machine-readable form.

A MARC record is composed of three elements: the record structure, the content designation, and the data content of the record. The record structure is an implementation of the international standard Format for Information Exchange (ISO 2709) and its American counterpart, Bibliographic Information Interchange (ANSI/NISO Z39.2). The content designation--the codes and conventions established explicitly to identify and further characterize the data elements within a record and to support the manipulation of that data--is defined by each of the MARC formats. The content of the data elements that comprise a MARC record is usually defined by standards outside the formats. Examples are the International Standard Bibliographic Description (ISBD), Anglo-American Cataloguing Rules, Library of Congress Subject Headings (LCSH), or other cataloging rules, subject thesauri, and classification schedules used by the organization that creates a record. The content of certain coded data elements is defined in the MARC formats (e.g., the Leader, field 008).

The MARC 21 Format for Authority Data: Including Guidelines for Content Designation defines the codes and conventions (tags, indicators, subfield codes, and coded values that identify the data elements in MARC authority records). This document is intended for the use of personnel involved in the creation and maintenance of authority records, as well as those involved in the design and maintenance of systems for communication and processing of bibliographic records. This documentation is also available online, including a concise version and a simple field list at: www.loc.gov/marc/.


SCOPE OF THE AUTHORITY FORMAT

The MARC 21 Format for Authority Data is designed to be a carrier for information concerning the authorized forms of names, subjects, and subject subdivisions to be used in constructing access points in MARC records, the forms of these names, subjects, and subject subdivisions that should be used as references to the authorized forms, and the interrelationships among these forms. A name may be used as a main, added, series, or subject access entry.

The term name refers to:

personal names (X00) names of jurisdictions (X51)
corporate names (X10) uniform titles (X30)
meeting names (X11) name/title combinations

The term subject refers to:

topical terms (X50) topical terms, geographic names, and
geographic names (X51) genre/form terms with subject subdivisions
genre/form terms (X55) chronological terms (X48)
names with subject subdivisions uniform titles with subject subdivisions (X30)

A subject may be used only as a subject access entry.

The term subject subdivision refers to:

general subdivision terms (X80) geographic subdivision names (X81)
chronological subdivision terms (X82) form subdivision terms (X85)

A subject subdivision may be used with a name or subject lead element in an extended subject access entry. It may not be used as the lead element in a main, added, series, or subject access entry.

The MARC 21 Format for Authority Data also provides for information concerning the authorized forms of node labels. A node label is not assigned to documents as an indexing term.

Kinds of Authority Records

MARC authority records are distinguished from all other types of MARC records by the presence of code z (Authority data) in Leader/06 (Type of record). The formulation of a name, subject, subject subdivision, or node label heading in an authority record is based on generally accepted cataloging and thesaurus-building conventions (e.g., AACR 2, LCSH). The content of the remainder of the authority records follows the practice of the organization creating the record.

The MARC 21 Format for Authority Data identifies seven kinds of authority records in 008/09, (Kind of record):

Types of Headings

In a MARC authority record, a heading is the content of a 1XX, 4XX, or 5XX field that documents the form of heading used for indexing and retrieval or organizational purposes in a file. Two types of headings are defined in the authorities format:

Headings may be names, name/title combinations, uniform titles, chronological terms, topical terms, genre/form terms, subdivisions, extended subject headings, or node labels.

Heading Usage in Authority Records

The MARC 21 Format for Authority Data identifies three categories of heading usage in records: main or added entry (008/14); subject added entry (008/15); and series added entry (008/16). Only established headings may be used as the lead element of access points in bibliographic records. Name, name/title, and uniform title established headings may be appropriately used as any one, two, or three of the 008/14-16 usage categories. Topical term and extended subject headings may be used only as subject added entries. Subdivision headings may be used only in extended subject heading added entries.

Heading Usage in Authority Structures

A heading may be categorized as being suitable for either a name or a subject authority structure. Name, name/title, and uniform title headings that are formulated using descriptive cataloging conventions (008/10) are suitable for a name authority structure. Established forms of these types of headings are used in established heading (008/09, code a) and established heading and subdivision records (code f); unestablished forms are used in reference records (code b or c). Certain note and tracing and reference fields in the format are used only in records for headings suitable for name authority structures.

Name, name/title, uniform title, chronological, topical and genre/form term (and extended subject headings using these types of headings), and subdivision headings that are formulated using subject heading system/thesaurus building conventions (008/11) are suitable for a subject authority structure. Established forms of these types of headings are used in established heading (008/09, code a) and established heading and subdivision (code f) records; unestablished forms are used in subdivision (code d), reference (code b or c), reference and subdivision (code g), and node label (code e) records. Certain note and tracing and reference fields in the format are used only in records for headings suitable for subject authority structures.

Series Treatment Information

Authority records that contain a 1XX field that contains a uniform title or name/title heading for a series may also contain information concerning the treatment of that series should the heading be used in bibliographic records. The term series applies to the types of series identified in 008/12: monographic series, multipart items, series-like phrases, and titles of occasionally-analyzable serials. The data elements and fields that are used to record series treatment include three character positions in the 008 field; link, standard number, and call number fields in the 0XX range; and the series treatment information fields in the 64X range.


COMPONENTS OF AUTHORITY RECORDS

Description of Record Parts

A MARC authority record consists of three main components: the Leader, the Directory, and the variable fields. The following information summarizes the structure of a separate MARC record. More detail is provided in MARC 21 Specifications for Record Structure, Character Sets, and Exchange Media.

The variable data fields are grouped into blocks according to the first character of the tag, which with some exceptions identifies the function of the data within the record. The type of information in the field is identified by the remainder of the tag.

0XX Standard numbers, classification numbers, codes
1XX Headings (established and unestablished)
2XX Complex see references
3XX Complex see also references
4XX See from tracings
5XX See also from tracings
6XX Treatment decisions, notes
7XX Linking entries
8XX Alternate graphics
9XX Reserved for local implementation

Within the 1XX, 4XX, 6XX, 7XX and 8XX blocks, certain parallels of content designation are usually preserved. The following meanings, with some exceptions, are given to the final two characters of the tag of fields:

X00 Personal names X51 Geographic names
X10 Corporate names X55 Genre/form terms
X11 Meeting names X80 General subdivisions
X30 Uniform titles X81 Geographic subdivisions
X48 Chronological terms X82 Chronological subdivisions
X50 Topical terms X85 Form subdivisions

Within variable data fields, the following two kinds of content designation are used:

Multiscript Authority Records

A MARC authority record may contain data in multiple scripts. One script may be considered the primary script of the data content of the record, even though other scripts are also used for data content. (Note: ASCII is used for the structure elements of the record, with most coded data also specified within the ASCII range of characters). General models for multiscript data are described in Appendix C, along with several full record examples.

Field and Subfield Repeatability

Theoretically, all fields and subfields may be repeated. The nature of the data, however, often precludes repetition. For example, an authority record may contain only one 1XX field; a field 100 may contain only one subfield $a (Personal name) but may contain more than one subfield $c (Titles and other words associated with a name). The repeatability or non-repeatability of each field and subfield is specified in the format.

Field Linking

Fields in the record may be specially linked using a generally-applicable field linking technique. The technique relies upon the syntax of data in subfield $8 (Field link and sequence number) to identify the linked fields. The structure and syntax for the field link and sequence number subfield are described in Appendix A.

Fill Character and Related Values

A fill character (ASCII 7C hex), represented in this document as a vertical bar (|), may be used in authority records in field 008, and subfield $w of the 4XX and 5XX tracing and 700-785 linking entry fields. A fill character may not be used in the Leader, or in tags, indicators, or subfield codes. The use of the fill character in records contributed to a national database may also be dependent upon the national level requirements specified for each data element. The presence of a fill character in an authority record indicates that the format specifies a code to be used but the creator of the record has decided not to attempt to supply a code.

Code u (Unknown or unspecified) when it is defined indicates that the creator of the record attempted to supply a code but was unable to determine what the appropriate code should be.

Code n (Not applicable) is defined in many coded positions to indicate that the characteristic defined by the position is not applicable to a specific type of item or kind of record.

Display Constants

A display constant is a term, phrase, spacing, or punctuation convention that may be system generated under prescribed circumstances in order to make a visual presentation of data in a record more meaningful to a user. In the authority format certain field tags (e.g., field 770, Supplement/Special Issue Entry), indicators (e.g. the 4XX and 5XX tracing fields), and subfield codes (e.g., the subject subdivision subfields $v, $x, $y, and $z in an extended subject heading), and coded values (e.g., tracings control subfield $w/0, Special relationship) may be used to generate specific display constants. The use of display constants is determined by each organization or system. Examples of display constants are provided under Input Conventions in the field descriptions.

Record Content Responsibility

The MARC 21 Format for Authority Data serves as a vehicle for authority data of all types from any organization. In general, the responsibility for the data content, content designation, and transcription of authority data within a MARC record may be determined by examination of the field indicated in the responsible parties section below. The data content of certain data elements, however, is restricted when the element is an agency-assigned or a controlled-list data element.

Responsible Parties

In unmodified records, the organization identified as the original cataloging source in 008/39 and/or 040 $a is responsible for the content of the record. The organization identified as the transcribing agency in field 040 $c is responsible for the content designation and transcription of the data.

In modified records, the organizations identified in 040 $a and $d (Modifying agency) are collectively responsible for the content of the record. Organizations identified as transcribing or modifying agencies in field 040 $c and $d are collectively responsible for the content designation and transcription of the data.

Agency-assigned Data Elements

An agency-assigned data element is one whose content is determined by a designated agency and is the responsibility of that agency, e.g., field 010 (Library of Congress Control Number). While it is usually input by the designated agency, it may be transcribed by another organization.

Controlled-list Data Elements

Certain data elements contain data from controlled lists maintained by designated agencies, e.g., the MARC Code List for Geographic Areas in field 043 (Geographic Area Code). These elements are indicated at the field or subfield level in MARC 21 and only values from the designated lists may be used. If a change or addition is desirable for a list, the maintenance agency for the list should be consulted.

Record Level Requirements

User groups may have full level and minimal level record requirements to promote consistency across cataloging agencies. These should be widely publicized for all possible interchange partners to be aware.


ORGANIZATION OF THIS DOCUMENT

Main Parts

MARC 21 Format for Authority Data consists of a Summary Statement of Content Designators followed by a detailed presentation of each content designator. Following the descriptions of the Leader and the Directory, the variable control fields are arranged in field tag order (001-008). The variable data fields are presented in the following groupings in order to bring together fields that serve related functions:

Appendixes to this document provide information about several control subfields (Appendix A), full level record examples (Appendix B), multiscript record examples (Appendix C), an alphabetical listing of ambiguous headings with suggested tagging (Appendix D), a multilingual list of initial definite and indefinite articles (Appendix E), lists of changes to the format since the last edition or update (Appendix F), and a list of organization code sources (Appendix G).

General Information Sections

To avoid repetition, general information sections are provided for groups of fields with similar characteristics. These general information sections provide instructions for the content designators that are common to each field in the group. The description for each of the fields refers back to the general information section for that group and to any related general information section.

To reduce repetition, the X-- General Information section is provided for types of headings (X00 Personal Names; X10 Corporate Names; X11 Meeting Names; X30 Uniform Titles, X48 Chronological Terms, X50 Topical Terms; X51 Geographic Names; X55 Genre/Form terms; X80 General Subdivisions; X81 Geographic Subdivisions; X82 Chronological Subdivisions; X85 Form Subdivisions). These general information sections provide instructions for the content designators that are common to each type of personal heading whether it is used in a 1XX heading, 4XX see from tracing or 5XX see also from tracing field, or a 7XX heading linking entry field. The description for each of the individual fields (i.e., 100, 600, 700, 800) refers back to the X-- General Information section for that type of heading.

A Tracing and Reference Fields−General Information section describes the use of the tracing fields (4XX and 5XX fields) and the various reference note fields (field 260, 360, and fields 663-666) in constructing displays of cross references from these fields. It also provides instructions for applying subfield $i (Relationship information) and subfield $w (Control subfield) in the 4XX and 5XX fields. The description for each of the reference note fields contains the detailed instructions for the content designators for the field. Reference is made to the Tracing and Reference Fields−General Information section only for cross reference display descriptions. Descriptions for the 4XX and 5XX fields refer to both the related X-- General Information section and the Tracing and reference fields section for content designator instructions.

A 7XX Heading Linking Entries−General Information section describes the use of the linking fields and provides instructions for applying the second indicator (Subject heading system/thesaurus) and subfield $0 (Record control number), subfield $w (Control subfield), subfield $2 (Source of heading or term), and subfield $8 (Field Link and sequence number). The individual descriptions for fields 700-785 list all of the content designators for each field and refer to both the general information section for the corresponding type of heading and to the 7XX general information section for application guidelines. The first indicator position and all of the subfield codes for field 788 (Complex Linking Entry Data) are fully described in the field 788 description.

Components of the Detailed Descriptions

A detailed description may consist of six parts: content designator listing; character position or field definition and scope; guidelines for applying content designators, with examples; input conventions; and content designator history.

The content designator listing area presents

For the Leader and the variable control fields, the list gives the name of the character position and any defined coded value. For the variable data fields, the list gives the name of the indicator positions and any defined coded values and the name of the subfield codes and any defined coded values. For all variable fields, the repeatability/nonrepeatability code at the field level specifies whether the field may be repeated in a record. For variable data fields, the subfield repeatability code specifies whether the subfield code may be repeated within a field.

The character position or field definition and scope area describes the contents of the character position or field, the appropriateness of its use in specific kinds of authority records, and gives other information, such as field repeatability in particular circumstances, the use of required lists or rules in formulating the data, etc.

The guidelines for applying content designators area describes the content and scope of each coded value, indicator, or subfield code and gives other information, such as appropriateness for use and repeatability in certain circumstances. Examples showing the use of the content designator are provided immediately following the description. The examples illustrate the application of specific MARC content designation. The data may be fuller or less full than would be used in actual cataloging practice. Most of the examples reflect the application of AACR 2 and ISBD; however, some reflect a generalized MARC application. Other examples illustrate specific points. In the X–General Information sections, the 1XX heading field examples usually illustrate the use of the content designators in a 4XX or 5XX tracing field as well. Neither field terminators nor record terminators are shown in the examples used in the MARC 21 Format for Authority Data.

The input conventions area provides general guidance for the application of the content designators, and for such things as punctuation, spacing, and the use of display constants. The input conventions clarify MARC punctuation practices especially with respect to final punctuation. In the discussion of punctuation practices, mark of punctuation is a period (.), a question mark (?), an exclamation mark (!), or a hyphen (-).

The content designator history area provides a record of significant content designator changes. The types of changes that are included are:

In the MARC formats, a distinction is made between obsolete and deleted content designators. An obsolete content designator is one that may have been used in MARC records and that may continue to appear in records created prior to the date it was made obsolete. Obsolete content designators are not used in new records. An obsolete content designator is recorded in the Content Designator History area. Content designation instructions are provided for retrospective conversion of records having data elements that would have been identified by the obsolete content designator. A deleted content designator is not recorded in the history area and will no longer appear anywhere in the MARC documentation. A content designator that had been reserved in MARC but has not been defined, or one that had been defined but is known with near certainty not to have been used, may be deleted from the format. A deleted content designator is available for redefinition in a format. A deleted content designator is available for redefinition in a format.

Typographical Conventions

Throughout this document, the following typographical conventions are used:


Link disclaimer

STANDARDS AND OTHER DOCUMENTS RELATED TO THIS FORMAT

The MARC 21 Format for Authority Data should be used with the following standards and related documentation. When a standard is applicable to data in specific fields of the format, the fields are given in brackets following the citation.

National and International Standards:

ISO publications may be obtained from the International Organization for Standardization (ISO) and their agents; and ANSI/NISO Z39 publications may be obtained from the National Information Standards Organization (NISO).

Character set standards are specified in MARC 21 Specifications for Record Structure, Character Sets, and Exchange Media.

MARC Standards and other related publications:

These publications are available from the Library of Congress, Cataloging Distribution Service, Washington, DC 20541, USA (Worldwide distribution). Where indicated these publications are available on the Internet.


SUPERSEDED DOCUMENTATION

This document supersedes the most recent editions of the USMARC Format for Authority Data and the Canadian MARC Communication Format: Authorities. With alignment of these formats in 1997, a single edition of the format could be issued.

USMARC Documentation

MARC 21 supersedes the 1993 edition of USMARC Format for Authority Data: Including Guidelines for Content Designation and updates No. 1 (July 1995),and No. 2 (March 1997) to that edition. With Update No.2 the USMARC and CAN/MARC formats were identical format specifications. The 1993 edition superseded the 1987 edition of the format and its four updates published between 1988 and 1991. The 1987 edition incorporated the base text of the 1976 edition and subsequent updates published under the title Authorities: A MARC Format.

CAN/MARC Documentation

MARC 21 supersedes the 1988 edition of Canadian MARC Communication Format: Authorities.


DOCUMENTATION MAINTENANCE

The MARC 21 Format for Authority Data is prepared by the Network Development and MARC Standards Office, Library of Congress, in cooperation with Content Management Division, Library and Archives Canada (previously National Library of Canada) and Bibliographic Standards and Systems, British Library. Please direct any questions related to the content of this document to one of the following:

Network Development and MARC Standards Office
Library of Congress
101 Independence Avenue, S.E.
Washington, DC 20540-4402, USA
Fax: +1-202-707-0115
Email: ndmso@loc.gov

Content Management Division
Library and Archives Canada
395 Wellington St.
Ottawa, Ontario K1A 0N4, Canada
Fax: +1-819-934-4388
Email: marc@bac-lac.gc.ca

Bibliographic Standards and Systems
The British Library
Boston Spa Wetherby
West Yorkshire LS23 7BQ, United Kingdom
Fax: +44 (0) 1937 546586
Email: bss-info@bl.uk

The MARC 21 Format for Authority Data is organized on a field-by-field basis with each field separately paged to facilitate the updating of fields. Periodic updates of new and replacement pages for the base text and cumulated versions of the base text will be available from the Cataloging Distribution Service, Library of Congress, Washington, DC 20541-5017, USA (Worldwide distribution) and available in Canada from Publishing and Depository Services, Public Works and Government Services Canada (PWGSC), Ottawa, Ontario K1A 0S5, Canada (Canadian distribution). Their availability will be announced on the Library of Congress MARC website, the Library and Archives Canada MARC website, on listservs, and through press releases to the library press and to those who purchase the initial base volume. Updates are also available on standing order from the Library of Congress and the Canadian Government Publishing-PWGSC. This publication and all updates are supplied to all purchasers of the Library of Congress MARC Distribution Service files of authority records as part of their MARC record subscription.


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