APA-referens (7:e uppl.)

Hobbs, G. M. (1972). Practical mathematics (3rd.ed.). American technical.

Chicago-referens (17:e uppl.)

Hobbs, Glen M. Practical Mathematics. 3rd.ed. Illinois: American technical, 1972.

MLA-referens (9:e uppl.)

Hobbs, Glen M. Practical Mathematics. 3rd.ed. American technical, 1972.