APA-referens (7:e uppl.)

Letchford, S. (1977). Business mathematics and statistics (2nd.ed.). Donnington.

Chicago-referens (17:e uppl.)

Letchford, S. Business Mathematics and Statistics. 2nd.ed. London: Donnington, 1977.

MLA-referens (9:e uppl.)

Letchford, S. Business Mathematics and Statistics. 2nd.ed. Donnington, 1977.