540n (ISN)
- Field number
- 540
- Indicator
- n
- Repeatable
- no
- Content
- International Standard Book Number (ISBN), International Standard Music Number (ISMN), International Standard Serial Number (ISSN) or European Article Number (EAN), each formally (technically) valid
- MARC21
- 020 (external site) $a; 024 (external site) $a for ISMN and ISSN
This field holds the ISBN (formally correct), the ISMN (formally correct), the ISSN (formally correct) or the EAN (formally correct).
The ISBN is introduced by the character sequence ISBN, whichever ISBN format is used.
Its individual parts — prefix, group number, publisher number, title number and check
digit — should be separated by hyphens.
The ISMN is introduced by the character sequence ISMN. Its individual parts — group
number, publisher number, title number and check digit — should be separated by hyphens.
The ISSN is introduced by the character sequence ISSN. The two parts of the ISSN are
separated by a hyphen.
The EAN is introduced by the character sequence EAN.
Examples
ISBN 3-87318-556-3
ISBN 978-3-87318-556-2
ISMN M-321-76546-7
ISSN 0044-2909