Engle, T. L. (1958). Psychology: Its principles and application. Harcourt, Brace.
Cita Chicago (17th ed.)Engle, T. L. Psychology: Its Principles and Application. N. Y: Harcourt, Brace, 1958.
Cita MLA (9th ed.)Engle, T. L. Psychology: Its Principles and Application. Harcourt, Brace, 1958.
Atenció: Aquestes cites poden no estar 100% correctes.