Citazione Stile APA (7a Edizione)

Trahan, M., & Gray, P. (1991). Focus on psychology: A guide to mastering Peter Gray's psychology. Worth.

Citazione stile Chigago Style (17a edizione)

Trahan, Mary, e Peter Gray. Focus on Psychology: A Guide to Mastering Peter Gray's Psychology. New York: Worth, 1991.

Citatione MLA (9a ed.)

Trahan, Mary, e Peter Gray. Focus on Psychology: A Guide to Mastering Peter Gray's Psychology. Worth, 1991.