APA-referens (7:e uppl.)

Sommer, R. (1997). A practical guide to behavioral research: Tools and techniques (4th ed.). OUP.

Chicago-referens (17:e uppl.)

Sommer, Robert. A Practical Guide to Behavioral Research: Tools and Techniques. 4th ed. New York: OUP, 1997.

MLA-referens (9:e uppl.)

Sommer, Robert. A Practical Guide to Behavioral Research: Tools and Techniques. 4th ed. OUP, 1997.