APA-referens (7:e uppl.)

(1987). Walford's guide to reference material (4th ed.). Library Association.

Chicago-referens (17:e uppl.)

Walford's Guide to Reference Material. 4th ed. London: Library Association, 1987.

MLA-referens (9:e uppl.)

Walford's Guide to Reference Material. 4th ed. Library Association, 1987.