Spear, P. D., Baker, T. B., & Penrod, S. D. (1988). Psychology: Perspectives on behavior. Wiley.
Cita Chicago (17th ed.)Spear, Peter D., Timothy B. Baker, i Steven D. Penrod. Psychology: Perspectives on Behavior. New York: Wiley, 1988.
Cita MLA (9th ed.)Spear, Peter D., et al. Psychology: Perspectives on Behavior. Wiley, 1988.
Atenció: Aquestes cites poden no estar 100% correctes.