CBS MARC fields that are important for linking
There are two CBS MARC tags that play a crucial role in PPN linking.
|Description||CBS MARC /
|0100||003@||Record Control Number (PPN)||$0 / $0||Record Control Number (PPN)||Important for bibliographic and authority records|
|0500||002@||Bibliographic type and status||$0 / $0||Bibliographic type and status||Value on second position only relevant for linking of bibliographic records|
Additional values for position 2 of field 0500 / 002@ in bibliographic records
The values in the next table are not used in "standard" MARC 21. These values are relevant when a library decides to use the linking features that are part of the CBS software and configuration. So, when a library only uses the "standard" MARC 21 elements, next values can be ignored by the cataloguer. The non-MARC 21 values use a capital letter; the MARC 21 values use a small letter on the second position of field 0500 / 002@.
|Pos. 2 of
tag 0500 / 002@
|A||Umbrella record of series|
|B||Part of a series1|
|E||Umbrella record of multivolume|
|F||Strong sub-umbrella record of multivolume|
|G||Weak sub-umbrella record of multivolume|
|H||Strong part of a multivolume publication|
|I||Weak part of a multivolume publication|
|J||Strong part of a multivolume publication in a series|
|K||Weak part of a multivolume publication in a series|
|X||Expression entity (cf. IFLA LRM)|
|W||Work entity (cf. IFLA LRM)|
- An umbrella record is a record that describes a series or a multivolume as such.
- A sub-umbrella record is a record that describes a subseries or a “section” of a multivolume as such.
- A part record is a record that describes a part of a series or a multivolume
Points of interest:
- No special code(s) is/are defined when 76X-78X - Linking Entry Fields - are used.
- Special attention needs to be paid e.g. to the CBS MARC 21 export. The values on position 2 of field 0500 / 002@ for title records can differ from the values used in the Leader, position 7 - Bibliographic level -.2
LNKDEF configuration file
The configuration file marc21_common_lnkdef.asc is called the LNKDEF.
The LNKDEF configuration file defines the following:
- Validation: if one is allowed to add a PPN in subfield $Z / $9 of a tag.
- How to find candidate records for linking.
- Which material types in tag 0500 subfield $0 / 002@ subfield $0 may be changed into one another.
- How to unlink a tag.
Thus, in this configuration file several options are available. The most important are:
- addLink=replace-$Sx Replace all subfields by PICA+ subfields $9 (PPN) except $S and $x
- addLink=replace+$ab Replace PICA+ subfields $a and $b by $9 (PPN)
The value of the addLink option needs to be synchronized with the (semantic) validation. I.e. when PICA+ subfield $9 is part of a field, several subfields are not allowed in the field at the same time. This must be arranged in the validation.
Linking is allowed within the same level only, i.e. main/master level tags may only be linked to bibliographic and authority records on main/master level; local level tags of e.g. subject headings may be linked only to an authority file on local level and not to an authority file on main/master level.
Expansion configuration files
In the expansion configuration files, the subfields that are replaced by the PPN, need to be generated by the expansion.
When there is a $Z / $9 expansion, the corresponding subfields are replaced, and not kept in the field.
Of course, it is possible that a field contains an expansion besides additional subfields, like subfields $4 - Relationship - in e.g. tag 100 - Main Entry-Personal Name - or subfield v - Volume number/sequential designation - in field 830 - Series Added Entry-Uniform Title -.
CBS MARC 21 indexes
There is a relation between the indexes on one hand and the LNKDEF configuration file and click effects on the other hand. The index type, the key type and the mnemonic are part of the LNKDEF file. And search attributes (ikt’s) are needed for the click effects.
Family indexes make it possible to use the commands fam, rel, rel nt, rel bt, rel rr.
- Horizontal relations between bibliographic records: title-title links - main level
- Vertical relations between bibliographic records: title-title links - main level
- Horizontal relations between authority records: authority-authority links - main level
The function famsort in family( $9, "" ) may have consequences for the syntax of several tags, when a separate sorting subfield is needed.3
Relation indexes make it possible to use the command "rel tt".
There are several kinds of links:
- Bibliographic records: title-authority links - main level
- Bibliographic records: title-authority links - local level
To be able to click e.g. on a PPN link, we need two versions of a html configuration file: html related to WinIBW and webhtml related to WebGGC and CCWeb.
Both the bibliographic and the authority (semantic) validation need to be adapted. When a PPN ($Z / $9) is present in a certain field, several subfields are not allowed at the same time, when they are part of the expansion.