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MARC PROPOSAL NO. 2023-06

DATE: May 25, 2023
REVISED:

NAME: Defining a New Field for Cluster ISSNs in the MARC 21 Bibliographic, Authority, and Holdings Formats

SOURCE: ISSN Review Group

SUMMARY: This paper proposes the creation of a new MARC field 023 in the MARC 21 Bibliographic, Authority, and Holdings formats to store Cluster ISSNs. Cluster ISSNs, such as ISSN-L, identify a group of related resources as defined in ISO 3297:2020.

KEYWORDS: Field 023 (AD, BD, HD); International Standard Serial Number (AD, BD, HD); Cluster ISSN (AD, BD, HD); ISSN (AD, BD, HD); Linking ISSN (AD, BD, HD); ISSN-L (AD, BD, HD); ISSN-H (AD, BD, HD)

RELATED: 2021-DP07; 2007-DP032007-052020-DP112021-04

STATUS/COMMENTS:
05/25/23 – Made available to the MARC community for discussion.

06/28/23 – Results of MARC Advisory Committee discussion: Approved as submitted, with the usage guidelines for subfields $0 and $1 to be determined by the community at a later date.

10/31/23 – Results of MARC Steering Group review - Agreed with the MAC decision.


Proposal No. 2023-06: Defining a New Field for Cluster ISSNs

1. BACKGROUND

Cluster ISSN is a new concept defined in ISO 3297:2020. Cluster ISSNs are identifiers that allow an ISSN designated by a specific prefix, e.g., ISSN-L 0302-9743, to identify a group of related continuing resources. This proposal is to define a new repeatable field, field 023, to provide a field that is distinct from the ISSN field (022) for this separate data element as ISO 3297 recommends. Another goal is to allow the URIs associated with each Cluster ISSN to be linked unambiguously with their corresponding Cluster ISSN. The ISSN International Centre is committed to using URIs whenever possible. The ISSN-L was the first example of a Cluster ISSN, one that provides a single identifier for the ISSNs assigned to the various medium versions of a continuing resource. ISSN-L is currently recorded in MARC field 022 $l. During the January 2021 MAC meeting, when URI subfields $0 and $1 were approved for field 022, concerns were raised that it might be difficult to know which ISSN (ISSN or ISSN-L) the URIs pertained to. Anticipation of future Cluster ISSNs with their associated URIs necessitates a new repeatable field to provide a separate field for each Cluster ISSN and its associated URIs.

The most recent revision of the International Standard, ISO 3297, Information and Documentation - International Standard Serial Number (ISSN), was published in June 2022 following its adoption as the seventh edition of the ISO ISSN Standard by the ISO Member Bodies. One outcome of the sixth edition of ISO 3297 (of which the seventh edition is a slight revision) was the concept of Cluster ISSN, which expanded the grouping of ISSNs exemplified by the Linking ISSN (ISSN-L) to provide for the identification of additional specific groups of ISSN, such as those comprising the title history of a publication linked by predecessor and successor title relationships.

1.1. Definition

In ISO 3297:2022, section 3.4.1 defines Cluster ISSN as an ISSN assigned to group of continuing resources related to each other. The ISSN International Center has now developed the History ISSN, abbreviated ISSN-H, which also has the structure of an 8-digit unique number but is prefixed by ISSN-H and does not repeat any of the ISSNs which are in the cluster. It clusters the ISSNs of sequential titles of a continuing resource over time. The result is a unique ISSN and accompanying URI for the title history of a continuing resource.

1.2. Technical Construction of ISSN-H

Thje ISSN International Centre will conduct a retrospective project to assign ISSN-H to the clusters linked by preceding and succeeding titles including all corresponding medium versions in the ISSN Register (the database that underlies the ISSN Portal). The ISSN International Centre will centralize the ongoing creation of Cluster ISSNs as incoming ISSN data from ISSN national centers is processed into MARC 21 records for inclusion in the ISSN Register. If a new ISSN is assigned to a continuing resource and the Register record for this new ISSN includes a MARC field 780 (Preceding Entry) and/or 785 (Succeeding Entry), its record and the related Register record(s) connected with a 776 field (Additional Physical Form Entry) will all be encoded with an ISSN-H in the 023 field. Future records linked by 780, 785, and the related 776 fields will all be encoded with the same ISSN-H. The diagram below represents the construction of an ISSN-H cluster.

Each title box represents a record that includes its own ISSN in field 022, but will also contain field 023 with the ISSN-H which is common to all records in the cluster.

1.3. Statistics

In the ISSN Register, the international database of 2.5 million ISSNs, there are approximately 400,000 ISSN-Ls which link at least 2 records each in the ISSN Register.  There will be approximately 208,000 History ISSNs, of which 193,000 would cluster 5 ISSN records or fewer.

2. DISCUSSION

The need for ISSN-L, the first Cluster ISSN, was based on a need expressed by the information community that went beyond the identification of specific medium versions of continuing resources already met by the ISSN. The additional need was for a grouping mechanism to bring together the various medium versions of a serial to facilitate content management and resolution services. Meeting this need led to the definition of ISSN-L in ISO 3297:2007. The 2020 revision of the ISSN standard (the sixth edition) recognized that there are other potential groups of continuing resources that are relevant to the community, such as a group that includes all preceding and succeeding titles of a continuing resource over time. Provision for additional Cluster ISSNs was therefore included in the revised ISO standard and carried into the 2022 seventh edition. The standard also specifies that future Cluster ISSNs will consist of their own unique 8-charcter ISSN, distinguished by a prefix that identifies the type of cluster, e.g., “ISSN-L” but unlike ISSN-L, future Cluster ISSNs will not repeat the ISSN of one of the members of the cluster.

Discussion Paper 2021-DP07, “Recording Cluster ISSNs…” presented in June 2021, used the hypothetical example of ISSN-F, a Family ISSN, to illustrate a possible future new Cluster ISSN. The boundaries of ISSN-F were unclear at that time and the extent of the "family" and use cases for it were questioned by MAC members and subsequently explored in the ISSN Review Group. What emerged from the Review Group discussion was a plan that replaced the Family ISSN concept with a plan for the History ISSN, ISSN-H, an identifier that will group the successive titles held by a publication over time.

A mechanism for grouping preceding and succeeding titles of serials has been of particular interest to the library community but also of interest to the indexing and publishing communities. In the interim following 2021-DP07, discussions were held with key vendors and indexers. One question concerned whether they would find the move of ISSN-L from field 022 to field 023 problematic; no objections were heard. Further discussions indicated that there was interest in various use cases for ISSN-H including graphic displays. One vendor, in particular, expressed considerable interest in the linked data capabilities of ISSN-H. ISSN-H as an identifier can help alleviate searching problems caused by new ISSNs assigned as a result of major title changes. A specific use case for the History ISSN is of interest to societies that wish to identify their conference publications with ISSN. Conference publications are notorious for changes in both the conference title and the proceedings title. As a result, a publication that its originator and users conceptualize as one publication might be represented by four or five different ISSNs and bibliographic records over its lifetime. The ISSN-H is designed to identify, retrieve, and potentially display a graphic of the entire cluster of preceding and succeeding conference publications.

The current ISO ISSN standard stipulates that the Cluster ISSN is a separate data element, distinct from the medium-specific ISSN.  In fact, this specification was already true since the inception of ISSN-L in 2007 but at the time, it seemed more expedient to add new subfields to field 022, the ISSN field. As the ISSN Portal implemented URIs for ISSNs, ISSN-L was given its own URI in the ISSN Portal and in the ISSN Linked Data Application Profile whose syntax is defined by the ISO standard. Additionally, discussions during the consideration of 2020-DP11 and Proposal 2021-04 to add URI subfields to field 022 brought forward the need to distinguish URIs for the Linking ISSN from the URIs for the ISSN in 022 $a. Defining a new repeatable field for Cluster ISSNs, field 023, will provide both a separate field for each Cluster ISSN as well as allow the appropriate URIs to be correctly associated with each Cluster ISSN.

2.1. Change in Field 022

Field 022 contains the following subfields: $a (ISSN)$y (Incorrect ISSN)$z (Canceled ISSN)$l (ISSN-L), for the linking ISSN; $m (Canceled ISSN-L); and $2 (Source), for the ISSN center code. If a new field is approved for Cluster ISSNs, it will be necessary to deprecate $l (ISSN-L) and $m (Canceled ISSN-L) in field 022 in favor of subfields $a (Cluster ISSN) and $z (Canceled Cluster ISSN) in the new field 023. Deprecating these fields in field 022 will clarify that any URIs in field 022 pertain to the ISSN in $a since any remaining ISSNs will be in $y or $z, subfields designated for incorrect or canceled ISSNs respectively that should not be associated in field 022 with URIs.

The ISSN International Centre (ISSN IC) is prepared to move all data in 022 $l and 022 $m in the ISSN Register to designated subfields in field 023. The new metadata production tool at the ISSN IC will facilitate this data transfer.

3. PROPOSED CHANGES

3.1. Define New Field 023

Define new field 023 for Cluster ISSN in the Bibliographic, Authority, and Holdings formats. The field will be used for specific Cluster ISSNs assigned by the ISSN IC.

Indicator values in Field 023 will be used to denote types of Cluster ISSN. At this time, ISSN-L has long been in use and ISSN-H has been developed. As new Cluster ISSNs are developed, new indicator values will be requested. It is not anticipated that more than a total of 10 types of Clusters will be needed, most likely fewer.

The field is defined as repeatable so that each specific Cluster ISSN can have its own field where any URI is associated only with that Cluster ISSN.

Define new field 023 in the Bibliographic, Authority and Holdings formats as follows:

023 -Cluster ISSN (R)

FIELD DEFINITION AND SCOPE
Field to record the Cluster ISSN, a mechanism defined in ISO 3297:2020 to provide for the identification of specific groups of ISSN, such as the various medium editions of a continuing resource, or serials related by preceding and succeeding title relationships.

Indicators

First Indicator Type of Cluster ISSN

0 - ISSN-L

Groups the various medium versions of a continuing resource. ISSN-L may be generated for display.

1 - ISSN-H

Groups the serials published under successive preceding and succeeding titles of the serial. ISSN-H may be generated for display.

Second indicatorUndefined

Subfield Codes

$a – Cluster ISSN (NR)

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.

$y – Incorrect Cluster ISSN (R)

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.

$z - Canceled Cluster ISSN (R)

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.

$0 - Authority record control number or standard identifier (NR)

A URI for the Cluster ISSN in subfield $a
See description of this subfield in Appendix A: Control Subfields.

$1 - Real World Object URI (R)

See description of this subfield in Appendix A: Control Subfields.

$2 - Source (NR)

ISSN center responsible for assigning and maintaining Cluster ISSNs and related data.

Code from: ISSN National Centres code list online at: www.issn.org, National Centres.

$6 - Linkage (NR)

See description of this subfield in Appendix A: Control Subfields.

$8 - Field link and sequence number (R)

See description of this subfield in Appendix A: Control Subfields.

3.2. Make Subfields $l and $m Obsolete in Field 022

In field 022 (International Serial Number) of the MARC 21 Bibliographic, Authority, and Holdings Formats, make the following subfields obsolete:

4. EXAMPLES

Note: The examples include hypothetical situations to illustrate usage.

Example 1: Linking ISSN

022 0 # $a 1476-4687 $2 2 $0 http://issn.org/resource/ISSN/1476-4687
023 0 # $a 0028-0836 $2 0 $0 http://issn.org/resource/ISSN-L/0028-0836
222 # # $a Nature $b (Basingstoke. Online)
245 1 # $a Nature.

Example 2: Linking ISSN with incorrect ISSN-L

022 0 # $a 0151-4105 $2 7 $0 http://issn.org/resource/ISSN/0151-4105#ISSN $0 https://urn.issn.org/URN:ISSN:0151-4105  
023 0 # $a 0151-4105 $2 0 $y 0048-7996 $1  http://issn.org/resource/ISSN-L/0151-4105  
222 # # $a Revue d'histoire des sciences
245 1 # $a Revue d'histoire des sciences.

Example 3: Linking ISSN with canceled ISSN-L

022 0 # $a 1043-0253 $2 1 $z 0147-8745 $0 http://issn.org/resource/ISSN/1043-0253
023 0 # $a 1043-0253 $2 0 $z 0147-8745 $0 http://issn.org/resource/ISSN-L/1043-0253
222 # 0 $a Fodor's USA
245 1 0 $a Fodor's USA.

Example 4: Linking ISSN on an authority record

130 # 0 $a Series in microscopy in materials science
022 0 # $a 2471-6367 $2 1 $0 http://issn.org/resource/ISSN/2471-6367   
023 0 # $a 2155-2320 $2 0 $0 http://issn.org/resource/ISSN-L/2155-2320   
222 # 0 $a Series in microscopy in materials science

Example 5: ISSN-H (history ISSN)

022 0 # $а 1063-3928 $2 1 $0 http://issn.org/resource/ISSN/1063-3928#ISSN
023 0 # $а 1063-3928 $2 0 $0 http://issn.org/resource/ISSN-L/1063-3928
023 1 # $a 9999-9999 $2 0 $0 http://issn.org/resource/ISSN-H/9999-9999
222 0 # $a Conference record of the IEEE Particle Accelerator Conference
245 0 0 $a Conference record of the IEEE Particle Accelerator Conference.
776 0 # $t Conference record of the IEEE Particle Accelerator Conference (Online) $x 2152-9647 $h cr
780 0 0 $t Proceedings of the IEEE Particle Accelerator Conference $x 1063-3936
785 0 0 $t Proceedings of the Particle Accelerator Conference $x 1529-7969

5. BIBFRAME DISCUSSION

Currently, BIBFRAME has a specific element at the Work level for "ISSN-L." It is a repeatable element that may be possible to change to "Cluster ISSN." The element could include a provision to indicate specific types of Cluster ISSNs, such as ISSN-L and ISSN-H.

6. SUMMARY OF PROPOSED CHANGES

6.1. Define new field 023 in the MARC 21 Bibliographic, Authority, and Holdings formats as follows (see Section 3.1. for a full description fo the field):

6.2. In Field 022 (International Serial Number) of the MARC 21 Bibliographic, Authority, and Holdings Formats, make the following subfields obsolete:


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