The Computer Assisted Reference Locator (CARL) is a computer-based information retrieval system which uses coordinate indexing. Objectives established in designing the system are: (1) simplicity of reference query and retrieval; (2) ease of system maintenance; and (3) adaptability for alternative computer systems. The source documents input into the system are not limited to published materials but could include such documents or files as lecture notes, documentation for computer programs, printed advertisements, equipment brochures, print or slide collections, and record or tape collections. The retrieval system could be adapted for home or personal use as well as for professional use. Data are input by keypunching, and include four types of entries: (1) header--author, year of publication, and first letter of title; (2) bibliographic citation; (3) author; and (4) subject keywords which are based on a controlled vocabulary and may include eighteen characters in length. The computer programs used for input preparation provide editing, sorting of cards, duplicating, and printing of keyword lists. Three systems programs are used for adding to the data base, query-retrieval, and change/maintenance. (MH)