Epstein, W., & Shontz, F. C. (1971). Psychology in progress. Holt.
Cita Chicago (17th ed.)Epstein, William, i Franklin C. Shontz. Psychology in Progress. New York: Holt, 1971.
Cita MLA (9th ed.)Epstein, William, i Franklin C. Shontz. Psychology in Progress. Holt, 1971.
Atenció: Aquestes cites poden no estar 100% correctes.