688 Subject Added Entry - Type of Entity Unspecified

Field definition and scope:

Field 688 contains a subject added entry in which the entity type of the entry element is unspecified.

The field is used if no information is provided to identify the type of entity to which the subject heading belongs.

Subject headings which are not constructed by standard thesaurus-building conventions are recorded in field 653 (Index Term - Uncontrolled).

Field 688 is repeatable.

Guidelines for applying content designators:

For indicator and subfield code definitions and examples, National-level (NLR) and Minimal-level (MLR) record requirements, and designator repeatability, see table below:

Position	Description	NLR	MLR	Repeatability
Field 688	Subject Added Entry - Type of Entity Unspecified	A	O	R
Indicator:
First	Undefined; contains a blank	M

Second	Source of name, title, or term	M
#	No information provided	A
7	Source specified in subfield $2	A

Subfield code:
$a	Name, title, or term			NR
$e	Relator term			R
$g	Miscellaneous information			R
$0	Authority record control number or standard number			R
$1	Real World Object URI			R
$2	Source of name, title, or term			NR
$3	Materials specified			NR
$4	Relationship			R
$6	Linkage	A	O	NR
$8	Field link and sequence number	O	O	R

Input conventions:

Content designator history:

Field 688 - Subject Added Entry - Type of Entity Unspecified [new,2019]