05. Leader and field 008 defined in the authority format
Leader and field 008 - Fixed-Length Data Elements - are used within the CBS MARC 21 format.
We have subdivided them in separate subfields within the context of the CBS MARC 21 cataloguing format.
In CBS MARC 21, blanks are indicated by hashes (#). In MARC 21, hashes often mean, but not always, "not specified". This is very important to be aware of when coded data is imported, exported or converted.
When a tag is filled (almost) completely with no "real" values, i.e. non-alphanumeric values, like hashes, pipe symbols, “unknown”, etc., this may have or will have consequences for the matching & merging process, e.g. in WorldCat.
When the Leader and/or field 008 on main level are missing during import of data into a CBS MARC 21 database, i.e. these are no part of the delivered records, both the Leader and/or field 008 are not generated. Then, both are no part of the records in the CBS MARC 21 database. During the export of this data to a MARC database, e.g. WorldCat, a 'default' Leader and tag 008 will be generated.
In this documentation, the expressions “When the value is present” and “When the values are present” mean that only “official” values are allowed. Non-official values are ignored during the import of records into a CBS MARC 21 database, and are not stored in this database.