Leader/18 Descriptive cataloging form

Leader/18 Descriptive cataloging form (Leader)

Character position definition and scope:

The Descriptive cataloging form character position contains a one-character alphanumeric code that indicates whether the record was formulated according to the Anglo-American Cataloguing Rules, 2nd Edition (AACR 2 ). The code also indicates whether the record exemplifies the rules of the International Standard Bibliographic Description (ISBD) (as reflected in particular sets of established cataloging rules) or only the punctuation practices of ISBD or none of the aspects of ISBD. Subfield $e (Description conventions) of field 040 (Cataloging Source) may contain additional information on the cataloging conventions used.

Record requirements (National-level and Minimal-level) for Leader/18 for all types of material : Mandatory.

Validity by material type : Leader/18 and its codes in the table below are valid for all types.

Code:	Descriptive cataloging form description:
#	Non-ISBD
a	AACR 2
i	ISBD
u	Unknown

Content designator history:

Code p (Record is in partial ISBD form) is obsolete. Defined 1974-1987. Treat as code i (ISBD) for current processing.

Code r (Record is in provisional form) is obsolete. Defined 1976-1981 for cataloging done according to AACR 1, chapter 12 revised. Treat as code i (ISBD) for current processing.

For information on other Leader positions, select:

Leader