Hjelle, L. A., & Ziegler, D. J. (1992). Personality theories: Basic assumptions, research, and applications (3rd.ed.). McGraw-hill.
Cita Chicago (17th ed.)Hjelle, Larry A., i Daniel J. Ziegler. Personality Theories: Basic Assumptions, Research, and Applications. 3rd.ed. New York: McGraw-hill, 1992.
Cita MLA (9th ed.)Hjelle, Larry A., i Daniel J. Ziegler. Personality Theories: Basic Assumptions, Research, and Applications. 3rd.ed. McGraw-hill, 1992.
Atenció: Aquestes cites poden no estar 100% correctes.