1. Altman, D. G. (1991). Practical statistics for medical research. Boca Raton, FL: Chapman and Hall/CRC.
2. American Psychological Association. (1987). Casebook on ethical principles of psychologists. Washington, DC: Author.
3. American Psychological Association. (1994). APA Adopts as Policy ‘Principles for Quality Undergraduate Psychology Programs’. Retrieved August 23, 2007, from http://www.apa.org/ed/stmary.html
4. American Psychological Association. (2002). Ethical Principles of Psychologists and Code of Conduct. The American Psychologist, 57, 1060–1073. doi: 10.1037/0003-066X.57.12.1060 .
5. American Psychological Association. (2007). APA guidelines for the undergraduate psychology major. Washington, DC: Author. Retrieved June 6, 2008, from http://www.apa.org/ed/resources.html