Cita APA (7th ed.)

Sommer, B. B., & Sommer, R. (1997). A practical guide to behavioral research: Tools and techniques (4th ed.). Oxford University Press.

Cita Chicago (17th ed.)

Sommer, Barbara Baker, i Robert Sommer. A Practical Guide to Behavioral Research: Tools and Techniques. 4th ed. New York: Oxford University Press, 1997.

Cita MLA (8th ed.)

Sommer, Barbara Baker, i Robert Sommer. A Practical Guide to Behavioral Research: Tools and Techniques. 4th ed. Oxford University Press, 1997.