Cita APA (7th ed.)

Walford, A. J. (1977). Guide to reference material (3rd ed.). The Library Association.

Cita Chicago (17th ed.)

Walford, Albert John. Guide to Reference Material. 3rd ed. London: The Library Association, 1977.

Cita MLA (9th ed.)

Walford, Albert John. Guide to Reference Material. 3rd ed. The Library Association, 1977.