An authority record may be:

• An established heading — where the 1XX contains an established heading, for example:

100 §aDickens, Charles,§d1812-1870

• A subdivision — where the 18X contains an unestablished partial heading that is meant to be used as a subject subdivision part of an established heading, for example:

182 §y16th Century

• An established heading and subdivision. This is a record in which the 15X field contains an established heading that may also be used as a subject subdivision with another established heading, for example:

151 §aAustralia

• A reference. This is a record in which the 100-155 fields contain a non preferred heading traced from the 4XX of an established record. In the example below, "150 §aCycleways” is traced from the established heading “Cycling tracks”. First the MARC display of the established heading: 

IRN    113870

LDR    *****cz   22*****o  4500

001    lib1173061532000

003    SANLIB

005    20020317170450.0

008    000211|n|fnannbaba|||||||||||a|ana|||||d

150    §aCycling tracks

450    §aCycleways

And then the non-preferred heading. Notice that there is no link back to the established heading.

IRN    113871

LDR    *****nz   22*****o  4500

001    lib1173061631000

003    SANLIB

005    20020317170451.0

008    000211nn|rnannbbbn|||||||||||n|ann|||||d

150    §aCycleways

The record type is coded into the 008 field and shown against “codes” in the full display for example:

Codes: Kind of record : Established heading and subdivision

       Type of subject subdivision : Topical

       Type of thesaurus : Library of Congress Subject Headings