Cita APA (7th ed.)

Walford, A. J. (1980). Walford's guide to reference material (4th ed.). The Library Association.

Cita Chicago (17th ed.)

Walford, A. J. Walford's Guide to Reference Material. 4th ed. London: The Library Association, 1980.

Cita MLA (9th ed.)

Walford, A. J. Walford's Guide to Reference Material. 4th ed. The Library Association, 1980.