URN

Description

Check whether the URN field (856) is present in the record. When invalid record is fixed, 856 field is added and URN is added to $u subfield either from 020 ISBN-field, or with URN-generator.

Note: Validator does not check contents of the existing 856-field, so a record with any field 856 is interpreted as valid, even if the field does not contain URN or URN does not match 020 ISBN in the record.

Note2: Validator creates just one URN field, even if the record has several 020 ISBN -fields.