1.	Brill, A.A. The Basic Writings of Sigmund Freud. New York: The Modern Library, 1995.
2.	Magill, Frank N., ed. Psychology Basics Volume 1. Pasadena, Ca: Salem Press Inc, 1993. P. 13-19, 212-242.
3.	Malott, Richard W., Donald L. Whaley and Maria E. Malott. Elementary Principles of Behavior. 3rd ed. Upper Saddle River, NJ: Prentice Hall Inc. 1997. P 1-17, 50-130.
4.	Matlin, Margaret, and Hugh J. Foley. Sensation and Perception. 4th ed. Needham Heights, Mass.: Allyn and Bacon, 1997.
5.	Wittig, Arno F. Schaum's Outline of Theories and Problems of Introduction to Psychology. New York: McGraw Hill Inc. 1977.
6.	Webber, Ann. Introduction to Psychology. New York: Harper Collins, 1991.
7.	MacGregor, Rob. The Everything Dream Book. Massachusetts: Adams Media Corporation, 1997.
8.	Fitzhenry, Robert. ed. The Harper Book of Quotations. 3rd ed. New York: HarperCollins Publisher, 1993.
9.	Fitzhenry, Robert. ed. The Harper Book of Quotations. 3rd ed. New York: HarperCollins Publisher, 1993.
10.	Hilton, James and Charles W. Perdue. Longman Mind Matters. CD-Rom. New York: Addison - Wesley Longman, 1999.
11.	Watkin, Grinny. "Sigmund Freud". Oct. 1996. < http://www.kcl.ac.uk/kis/schools/hums/philosophy/staff/Freud.html>. (June. 2000).