The History of Linking Devices.

TLDR: This article discussion is limited to the devices used as links for bibliographic relationships: multiple entries, cross-references, added entries, and entries based on multilevel description.

Abstract: The History of Linking Devices In the first two articles in this series, a taxonomy of bibliographic relationships was reported and an overview of the treatment of the various relationships in cataloging rules was presented. A review of principal sets of cataloging rules from Panizzi to the Anglo-American Cataloguing Rules, second edition (AACR2)[1] revealed an interesting evolution in the various linking devices used in library catalogs over the years. "Linking devices" are those specific devices within the catalog that connect or link bibliographic records for related items. We now turn to an examination of each device, indicating its specific use as a linking mechanism. Linking devices encompass the following: 1. Catalog entries Multiple entries Common main-entry headings Dash entries Analytical entries Cross-references See also references See references Added entries Name, title, and series added entries Multilevel description 2. Uniform titles 3. Other linking devices Notes, including contents, annotations of a library's holdings, etc. References to multiple entries or headings Edition statements Series statements Additions to the physical description Often a device used to show relationships is also used for other purposes. For example, an added entry heading is used to link two bibliographic records, but it may also act simply as an access point for one bibliographic record. In the first situation, it expresses a bibliographic relationship, while in the second it merely identifies an access point. In this article discussion is limited to the devices used as links for bibliographic relationships. CATALOG ENTRIES[2] Various types of catalog entries have been used as linking devices: multiple entries, cross-references, added entries, and entries based on multilevel description. It is probably not surprising that changes in such entries directly correspond to changes in the physical form of library catalogs. Just as catalogs emerged from inventory lists on clay tablets and progressed through handwritten card catalogs, typeset book catalogs, and printed or typed card catalogs to arrive at computerized, computer-output microform (COM) and online catalogs, so catalog entries have evolved from single, brief entries on a chronological list and progressed through single-author entries and cross-references in book catalogs, and more complex added entries in card catalogs, to arrive at the present records in machine-readable form based on the MARC format. Panizzi's rules, published in 1841, suited the then-predominant book and handwritten card catalogs. As a result of the economic restrictions on the size of book catalogs and the extensive time involved in writing cards for the handwritten card catalogs, Panizzi's rules called for a bibliographic item to be described in full only once, by means of an "entry." To provide more complete access to the entries and to make the catalog more than a mere finding list or inventory of the collection, the rules called for "cross-references." Panizzi's three classes of cross-references linked (1) name to name, (2) name to work, (3) work to work. The first class of cross-references referred the catalog user from a variant form of name to the form chosen for an "entry heading." The second class of cross-references directed the user to a catalog entry for a work from headings that might be considered equally as important as the main heading in accessing the entry. Such headings included personal, corporate, conference, and geographic names, as well as the names of works, i.e., titles. The third class served to direct the user from one work to another work, most commonly from parts of a work to the whole work in which they were contained. …