148 Heading - Chronological Term

Field definition and scope:

Field 148 contains a chronological term used as a heading in an established heading record, an established heading and subdivision record, a traced or an untraced reference record, or a reference and subdivision record. In an established heading record, field 148 contains the established form of a chronological term. In records for references, this field contains an unestablished form of a chronological term.

The National level record requirement for this field is Mandatory if applicable.

Field 148 is NOT repeatable.

Guidelines for applying content designators:

The content designators identify the subelements occurring in chronological term headings constructed according to generally accepted thesaurus-building conventions (e.g., Faceted Application of Subject Terminology (FAST)).

Chronological terms include dates that are used as the lead element of subject or added entry access fields in bibliographic records.

A chronological term that is authorized for use only as a subject subdivision part of an extended subject heading is contained in a 182 (Chronological Subdivision) field.

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

Position	Description	NLR	Repeatability
Field 148	Heading - Chronological Term	A	NR
Indicator:
First	Undefined; contains a blank	M
Second	Undefined; contains a blank	M

Subfield code:
$a	Chronological term	M	NR
$v	Form subdivision	A	R
$x	General subdivision	A	R
$y	Chronological subdivision	A	R
$z	Geographic subdivision	A	R
$6	Linkage	A	NR
$8	Field link and sequence number	O	R

See: Examples for this field.

Input conventions:

Punctuation

Spacing

Display constant

LC Guidelines:

148 Heading - Chronological Term