The 781 field is an optional field that NACO participants may provide in name authority records for geographic headings (151).  The 781 field indicates the correct form and MARC 21 coding for a geographic heading when it is used as a geographic subdivision in a subject heading on a bibliographic record.

NACO members wishing to use this field should consult DCM Section Z1 and SHM instruction sheets H 830 and H 835.

The code used in the second indicator of the 781 field is 0 (Library of Congress Subject Headings) and the subfield assignment is z (geographic subdivision).

Examples:

151 ## $a Westfield (N.Y.)

781 #0 $z New York (State) $z Westfield

151 ## $a Westfield (N.Y. : Town)

781 #0 $z New York (State) $z Westfield (Town)

Not all geographic headings in the LC/NAF are suitable for use as geographic subdivisions.  Subject practice does not subdivide geographically below the city level.

For headings that represent geographic entities within cities, such as city sections, a 667 subject usage note should be added with the wording:  "This heading is not valid for use as a geographic subdivision."

Examples:

151 ## $a Chelsea (London, England)

667 ## $a SUBJECT USAGE: This heading is not valid for use as a geographic subdivision.

151 ## $a Hong Kong

667 ## $a SUBJECT USAGE: This heading is not valid for use as a subject. Works about this place are entered under Hong Kong (China).

151 ## $a Hong Kong (China)

781 #0 $z China $z Hong Kong

Subject practice differs from descriptive practice in using only the heading that represents the latest name or status of a jurisdiction that has changed its name or status regardless of time period covered.  Such headings are coded "b" in fixed field 008/15 and have a 667 subject usage note.  NACO participants should not add 781 fields to these records.

See also:

Section I:  New Authority Records