The Library of Congress >> Especially for Librarians and Archivists >> Standards

MARC Standards

HOME >> MARC Development >> Discussion Paper List


DATE: December 20, 2012

NAME: Identifying Records from National Bibliographies in MARC 21 Bibliographic Format

SOURCE: OCLC National Libraries Working Group

SUMMARY: This paper explores possibilities for identifying records from national bibliographies.

KEYWORDS: Field 015 (BD); National Bibliography Number (BD); Field 042 (BD); Authentication Code (BD); Field 040 (BD); Cataloging Source (BD); National bibliographies (BD)


12/20/12 - Made available to the MARC community for discussion.

01/27/13 – Results of MARC Advisory Committee discussion: LC will create a specific and an unambiguous code that will identify a national bibliography in a record (in field 042). No need for changes in MARC documentation and no need to bring back as a proposal at this time. OCLC will then issue a statement on its rules for use of the code in Worldcat and the MARC listserv, and the rules for modification of records identified as national bibliography records.

Discussion Paper No. 2013-DP01: Identifying Records from National Bibliographies in the Bibliographic Format


Over the past three years, OCLC staff have had discussions with a working group of national libraries that contribute the records from their national bibliographies (as well as other cataloging they produce for materials that do not fall within the scope of the national bibliography).  Some of these national libraries also use OCLC WorldCat as a source of bibliographic data to be used in their own workflows and would prefer to use the authoritative records from a national bibliography wherever possible.  Topics which emerged from these discussions included: the variations in how national bibliography records can be (and are) coded, the need for easy identification of national bibliography records both by cataloging staff and for machine-processing purposes, and the need to distinguish clearly the records which are part of the national bibliography from those which describe other materials acquired by national library that may perhaps be cataloged less fully.  The working group, as a follow-up to these discussions, is to begin a discussion with the MARC 21 community on ways to achieve clearer coding that will benefit both the national libraries themselves and all cataloging users of the bibliographic data they produce.

MARC 21 does not provide an unambiguous method for identifying records from national bibliographies.  There is no explicit designation in a record although the designation might be derived from a combination of elements within a MARC record and a means to identify national libraries and agencies.  However, such a combination requires intelligence outside the MARC 21 record and will not work for all national bibliographies.  In some instances, there is absolutely no means by which to unambiguously flag a record using current MARC 21 encoding.  Records from national bibliographies are coded and distributed differently from one agency to another and there is a strong lack of similarity among them.


2.1. Currently Defined Elements
The following elements are among those that seem to be useful but each tag and combination of MARC 21 tags has its own shortcomings:

2.1.1. Field 042 (Authentication Code)

Currently defined in the Bibliographic format as:

Comments:  Field 042 is used for a variety of purposes, one of which includes designating a record that is part of the national bibliography, but the use of such coding does not address all national bibliographies.  The presence of a code authenticates a record in that it applies at the time the record was created or modified to match the national bibliography record.  The Croation National Bibliography seems to be the only national bibliography that has its own field 042 code.

Example:  croatica - Croatian National Bibliography

Code croatica signifies that the descriptive elements have been edited and all headings were verified against the relevant authority file to prepare the record for inclusion in the Croatian National Bibliography

2.1.2. Field 015 (National Bibliography Number)

Currently defined in the Bibliographic format as:

Comments: The presence of field 015 means only that the cataloging was derived from a record in a national bibliography and that the national bibliography entry contained a number identifying the resource.  It does not indicate that the cataloging data reflects the practices represented in the national bibliography.  Not all national bibliographies have a number that identifies the resource or the record.  Since libraries rely on the authority behind cataloging information in a national bibliography, the presence of this number is not adequate by itself.

In addition, the source of the number has not always been recorded in MARC 21 record.  Subfield $2 (Source) was added to the MARC 21 bibliographic format in 2001 but field 015 has been valid for use since the 1970’s.  Records created and distributed prior to 2001 do not include an explicit identification of the national bibliography.

2.1.3. Combined use of Field 040 (Cataloging Source) and 008/39 (Cataloging source code), with possible influence from Leader/17 (Encoding level)

Field 040 is currently defined in the Bibliographic format as:

Field 008/39 is currently defined in the Bibliographric format as:

Comments: Combined use of these two elements could indicate that the record is from a national organization or cooperative and which agency it is from.  In combination with field 015 (National Bibliography Number), they collectively are a strong indication that the record is from a national bibliography, but there is no guarantee that the record is from the national bibliography of the country that created the MARC record.  Some national agencies create more than one type of record, using the same coding in 008/39 and field 040; some records may be included in national bibliography and others only in the library’s catalog.  Encoding Level might help some but only marginally.

2.2. Discussion
Due to a history of several decades of inconsistent coding and identification of records in national bibliographies, none of these coding schemes will suffice for all national bibliographies.  What is needed is discrete and unambiguous coding that identifies a national bibliography version of a record.  Without an explicit designation, it is not easy or reasonable to apply specific processing to records from national bibliographies.  The flag should meet at a minimum the following requirements:

  1. Specific and unambiguous coding that indicates “This record is from a national bibliography”.
  2. Specific and unambiguous coding that indicates which national bibliography the record is in.
  3. Specific and unambiguous coding as to the completeness of the data, conformity to standards, and the cataloging agency.  Sometimes the identification of the standard should also be recorded in field 042.

In present MARC coding, all three requirements are not met, although ‘3’ is handled well in MARC now.  The first one is not met at all and the second one is only sometimes satisfied.


Several options may be available for identifying records from national bibliography–the basic data necessary includes: identification of the source of the record, its existence in a national bibliography, and identification of the national bibliography. The rules and standards used to create the record are also valuable but can be coded elsewhere in the record (042$a, 040$e, 008/18) without changes to the MARC 21 Bibliographic format.

  1. Expansion of field 042 authentication codes to identify each national bibliography’s records.  Each national bibliography could request its own codes.

    Advantages:  unambiguous identification of the rules used to create the record.

    Disadvantages: Processing the records in any kind of meaningful way would require being aware of what could be dozens of codes.  The maintenance of such a list could be problematic as is any such lengthy list that requires ongoing maintenance. In addition, conversions of large files of legacy data would be required if the coding is to be useful.

  2. Addition of a single, shared code to field 042 meaning ‘national bibliography record’.

    Advantages: unambiguous identification that a record is part of a national bibliography.  Easy to maintain and utilize a single identifier.

    Disadvantages: Additional information is needed to identify which national bibliography the record is from.  Knowing that a record is from a national bibliography is only the beginning of its provenance.

  3. Continue with current practice but each national agency must carefully craft and define its practices so recipients of their data can unambiguously identify the national bibliography records.  This places the burden on each recipient of records from multiple sources to identify the records in their systems.

    Advantages: Systems generating and distributing national bibliography records would have no change.

    Disadvantages: Development and upkeep of the code to identify national bibliography records would require staff time that could be spent on improving other services, including navigation and discovery services.  While some national bibliographies would be fairly straightforward, some are not.  Also, there is probably some commonality between some national libraries, but even the small group of libraries represented in the Working Group contains idiosyncratic variations that would require developer involvement to flag the records.  This option places the burden on the receiving system to interpret what the originating institution could explicitly provide.

HOME >> MARC Development >> Discussion Paper List

The Library of Congress >> Especially for Librarians and Archivists >> Standards
( 02/12/2013 )
Legal | External Link Disclaimer Contact Us