Citations or references to published bibliographic descriptions, reviews, abstracts, or indexes of the content of the described item.

Used to specify where an item has been cited or reviewed. Citations or references may be given in a brief form (i.e., using generally recognizable abbreviations, etc.). The actual text of a published description is not recorded in field 510 but rather in field 520 (Summary, Etc. Note).

For books and music, this field contains references to published descriptions of the item (e.g., descriptions of rare materials recorded in a brief, standardized format) or reviews (e.g., reviews in professional literature).

For continuing resources, this field is used to specify publications in which a continuing resource has been indexed and/or abstracted and the dates of coverage, if known. The indexing and abstracting services referenced are primarily those issued as continuing resources. Certain monographic titles, particularly those that are standard reference tools in a subject area or that cover periods of time not included in continuing publications, may also be given in this field.

For unpublished visual materials or graphic items collectively controlled, this field contains references to published descriptions of the work or collection. Citations to reviews of projected visual materials are also recorded in this field.

For mixed materials, this field contains references to publications in which abstracts, citations, descriptions, or indexes of the described materials have appeared.

Note that field 510 is used when the indexing and/or review is external to the item represented by the bibliographic record. Field 555 (Cumulative Index/Finding Aids Note) is used when an index is an integral part of the item. When the title of the source of the index, abstract, review, etc. changes, a separate field 510 is used for each title. When coverage changes, thus requiring a different value in the first indicator, a new field 510 with appropriate dates is added to the record.

Field 510 is repeatable for multiple source citations.

Citation/references notes are usually displayed and/or printed with an introductory term or phrase that is generated as a display constant based on the first indicator value.