This is a shortened version of the three volume "Walford's Guide to Reference Material", 5th edition: Volume 1, Science and Technology (1989), Volume 2, Social and historical sciences, philosophy and religion (1990), and Volume 3, Generalia, language and literature, the arts (1991). There are more than 3,000 entries, forming an updated compilation of what are considered to be the basic items in the main volumes, plus some more recent material up to April 1992. From its first edition the purpose of "Walford" has been to identify and evaluate the widest possible range of reference materials. In addition to the expected bibliographies, indexes, dictionaries, encyclopaedias and directories a number of important textbooks and manuals of general practice are included. Although the majority of items are reference "books", "Walford" is a guide to reference "material". Thus periodical articles, microforms, online and CD-ROM sources are all represented. Foreign-language works have been included where there is no satisfactory English alternative. Entries follow a subject arrangement based on the Universal Decimal Classification International Medium Edition of 1985 (BA1000M). Subject access for users unfamiliar with UDC is made easy with reference to the contents page, and entries are subdivided by form, place etc. There are full author/title indexes as well as subject indexes.