Cita APA (7th ed.)

Duffy, K. G. (1998). Psychology 98/99 (28th ed.). Dushkin/McGraw-Hill.

Cita Chicago (17th ed.)

Duffy, Karen G. Psychology 98/99. 28th ed. Guilford: Dushkin/McGraw-Hill, 1998.

Cita MLA (8th ed.)

Duffy, Karen G. Psychology 98/99. 28th ed. Dushkin/McGraw-Hill, 1998.