A comprehensive automated bibliographic control system has been developed by the New York Public Library. This system is unique in its use of an automated authority system and highly sophisticated machine filing algorithms. The primary aim was the rigorous control of established forms and their cross-reference structure. The original impetus for creation of the system, and its most highly visible product, is a photocomposed book catalog. The book catalog subsystem supplies automatic punctuation of condensed entries and contains the ability to produce cumulation/supplement book catalogs in installments without loss of control of the cross-referencing structure.
A description is given of the file organization and design of an on-line catalog suitable for automation of a library of one million books. A method of virtual hash addressing allows rapid search of the indexes to the catalog file. Storage of textual material in a compressed form allows considerable reduction in storage costs.