DATE: May 1, 1998

NAME: Definition of Subfield $0 for Record Control Number in the 7XX Fields in the USMARC Classification and Community Information Formats

SOURCE: Library of Congress

SUMMARY: This paper proposes changing the subfield for Record control number in the Classification and Community Information Formats. When subfield $0 was defined for Record control number in the USMARC Authority format as a result of the CAN/MARC harmonization changes, the other two formats were not included. This proposal attempts to remedy that oversight.

KEYWORDS: Subfield $0, in field 7XX (CD, CI); Record Control Number (CD, CI)

RELATED: 96-8,Part 5: 5XX, 7XX (Authority)


5/1/98 - Forwarded to the USMARC Advisory Group for discussion at the June 1998 MARBI meetings.

6/27/98 - Results of USMARC Advisory Group discussion - Approved as amended.
Subfield $w was deleted, rather than made obsolete, since it had not been used in the Classification or Community Information formats.

7/29/98 - Results of LC/NLC review - Agreed with the MARBI decisions.

PROPOSAL NO. 98-10: Subfield $0 for Record Control Number


Proposal No. 96-8 (CAN/MARC Changes for MARC Format Alignment) was considered by the USMARC Advisory Group in 1996 and 1997. As part of that proposal, subfield $0 was approved in the 5XX and 7XX fields in the USMARC Authority Format to link to the authority record for the entity in the field. In CAN/MARC, subfield $3 had been used for this purpose, but that field is defined in some formats as Materials specified in USMARC. However, Canada preferred a subfield in the numeric range because of the nature of the information.

That proposal was approved in February 1997. After an analysis of the different subfields used in the formats for Record control number LC staff noted that it would be better for both users and systems if the 7XX subfield for the authority Record control number were $0 in the Classification and Community Information Formats also.


The 7XX fields in the Classification, Community Information, Bibliographic and Authority Formats all contain 700-730 fields with the same content designation except for the Record control number. Subfield $w is defined for Record control number in Classification and Community Information to contain a record control number for the related authority record. The choice of subfield originally was consistent with what was used in the USMARC bibliographic format for Record control number in the linking entry fields (76X-78X) although those links are to bibliographic records, not to authority records. However, when the subfield was needed in the USMARC Authority format, subfield $w was not available, since it was defined as the Control subfield in fields 4XX, 5XX, and 7XX. At that time Record control number was defined as $v in field 7XX; after the Form subdivision was added to the authority format in 1995, the subfield for Record control number was changed to $u. It was then changed to $0 with the CAN/MARC harmonization proposals.

Subfield $w is defined as bibliographic Record control number in fields 76X, 77X, and 78X of Bibliographic and in field 856 in the Bibliographic, Classification, Community Information and Holdings formats. The subfield $w in those fields links to another bibliographic record, rather than to an authority record. With this change, for consistency in the future, links to bibliographic records would use $w for Record control number and links to authority records would use $0.


In the USMARC Classification and Community Information Formats:

- Define subfield $0 as Record control number in:

- Make subfield $w (Record control number) obsolete in the above fields

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