748 Established Heading Linking Entry - Chronological Term (R) (Variable Data Field)
Field 748 contains a chronological term that is equivalent to the 148 chronological term or 182 chronological subdivision heading field of the same record. It links headings within a system or from different thesauri or authority files.
The National level record requirement for this field is Optional.
Field 748 is 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 748 |
Established Heading Linking Entry - Chronological Term |
O |
R |
Indicator: |
|
|
|
First |
Undefined; contains a blank |
M |
|
|
|
|
|
Second |
M |
|
|
0 |
A |
|
|
1 |
A |
|
|
2 |
A |
|
|
3 |
A |
|
|
4 |
A |
|
|
5 |
A |
|
|
6 |
A |
|
|
7 |
A |
|
|
|
|
|
|
Subfield code: |
|
|
|
$a |
M |
NR |
|
$i |
A |
R |
|
$v |
A |
R |
|
$w |
A |
NR |
|
|
/0 Link display |
M |
|
|
A |
|
|
$x |
A |
R |
|
$y |
A |
R |
|
$z |
A |
R |
|
$0 |
A |
R |
|
$1 |
|
R |
|
$2 |
A |
NR |
|
$4 |
O |
R |
|
$5 |
A |
R |
|
$6 |
A |
NR |
|
$8 |
O |
R |
See: Examples for this field.
Display constant for X48 fields
Display constants for 7XX Linking Entries
748 - Established Heading Linking Entry - Chronological Term [new, 2002]
Subfield $i - Relationship information [new, 2014]
Subfield $0 - Record control number [redefined, 2010]
Subfield $w/1 - Replacement complexity [new, 2002]: In 2002, subfield $w/1 was defined with the following codes: a (Heading replacement does not require review); b (Heading replacement requires review); and n (Not applicable).
Subfield $1 - Real World Object URI [new, 2017]
Subfield $4 - Relationship code [new, 2014]
Subfield $4 - Relationship code [renamed, 2017] [redescribed, 2017]: Subfield $4 was renamed to Relationship and redescribed to allow for the recording of relationship URIs in addition to MARC and non-MARC codes.
LC Guidelines:
748 Established Heading Linking Entry - Chronological Term
Related MARC fields or documents:
X48 Chronological Terms - General Information
7XX Heading Linking Entries - General Information
Source Codes for Vocabularies, Rules, and Schemes:
Subject Heading and Term Source Codes
See also: