| First Indicator | Second Indicator |
|---|---|
| Type of Cluster ISSN 0 - ISSN-L 1 - ISSN-H |
Undefined # - Undefined |
| Subfield Codes | |
|---|---|
|
|
Field to record the Cluster ISSN, a mechanism first defined in ISO 3297:2020 to provide for the identification of specific groups of ISSN (International Standard Serial Number), such as the various medium editions of a continuing resource, or serials related by preceding and succeeding title relationships.
First Indicator - Type of Cluster ISSN
Groups the various medium versions of a continuing resource. ISSN-L may be generated for display.
Groups the serials published under successive preceding and succeeding titles of the serial. ISSN-H may be generated for display.
Second Indicator - Undefined
Undefined and contains a blank (#).
$a - Cluster ISSN
As designated by the ISSN International Centre, Cluster ISSNs group together resources with specific relationships to each other such as medium versions (ISSN-L), and clusters such as earlier and later titles (ISSN-H). The appropriate prefix for the ISSN type denoted by the first indicator value may be generated for display, for value 0: ISSN-L; for value 1: ISSN-H.
| 023 | 0#$a0028-0836$20 | ||||||||
| 023 | 0#$a1063-3928$20 | ||||||||
| 023 | 1#$a9999-9999$20 [ISSN-H (history ISSN)] |
||||||||
$y - Incorrect Cluster ISSN
Cluster ISSN that has been incorrectly associated with the continuing resource or incorrectly formatted on the resource. Each incorrect Cluster ISSN is contained in a separate $y.
E.g., ISSN-L (incorrect) may be generated for display.
| 023 | 0#$a0151-4105$20$y0048-7996 | ||||||||
$z - Canceled Cluster ISSN
Cluster ISSN that has been associated with the resource but subsequently canceled, often because a duplicate Cluster ISSN was assigned. Each canceled Cluster ISSN is contained in a separate $z.
E.g., ISSN-L (canceled) may be generated for display.
| 023 | 0#$a 1043-0253$20$z0147-8745 | ||||||||
$0 - Authority record control number or standard number
A URI for the Cluster ISSN in subfield $a.
See description of this subfield in Appendix A: Control Subfields.
$1 - Real World Object URI
See description of this subfield in Appendix A: Control Subfields.
$2 - Source
ISSN Center responsible for assigning and maintaining Cluster ISSNs and related data.
Code from: ISSN Manual, Annex 3: List of ISSN Centre codes [PDF, 199 KB].
$6 - Linkage
See description of this subfield in Appendix A: Control Subfields.
$8 - Field link and sequence number
See description of this subfield in Appendix A: Control Subfields.
Cluster ISSN Structure - A Cluster ISSN is an agency-assigned data element. Cluster ISSNs are assigned to continuing resource publications by the ISSN International Centre. Cluster ISSNs consist of a prefix followed by an ISSN that conforms to the basic ISSN structure: eight digits comprising two groups of four digits each, separated by a hyphen. Cluster ISSN-L, for example, consists of the prefix ISSN-L plus the ISSN issued to the first-registered publication in the cluster. ISSN-H, to be implemented in 2024, will consist of the prefix ISSN-H plus an ISSN that is newly assigned, and does not belong to any of the publications in the cluster.
The eighth digit of all ISSNs is a check digit used as a computer validity check; it consists of a number between 0 and 9 or an uppercase X (for the Arabic numeral 10).
A description of the ISSN and Cluster ISSN structure and the procedure for validation of the ISSN by calculating the check digit is in International Standard Serial Numbering (ISSN) (ISO 3297:2022).
Punctuation - Field 023 does not end with a period.
Display Constants
| ISSN-L | [associated with the content of subfield $a] |
| ISSN-H | [associated with the content of subfield $a] |
| ISSN-L (incorrect) | [associated with the content of subfield $y] |
| ISSN-H (incorrect) | [associated with the content of subfield $y] |
| ISSN-L (canceled) | [associated with the content of subfield $z] |
| ISSN-H (canceled) | [associated with the content of subfield $z] |
Cluster ISSNs should be displayed on an item with the appropriate prefix, currently ISSN-L or, in future, ISSN-H, followed by two groups of four digits separated by a hyphen. The hyphen separating the two groups of digits is carried in the MARC record. The initialisms ISSN-L and ISSN-H in combination with the terms (canceled) or (incorrect) are not input. They may be system-generated as display constants associated with the content of subfields $a, $y, and $z, respectively.
|
Content designated field:
|
|||||||||
| 023 | 0#$a0028-0836$20 | ||||||||
|
Display example: ISSN-L 0028-0836
|
|||||||||
|
Content designated field:
|
|||||||||
| 023 | 0#$a0151-4105$20$y0048-7996 | ||||||||
|
Display example: ISSN-L 0151-4105 ISSN- L (incorrect) 0048-7996
|
|||||||||