Shaughnessy, J. J., Zechmeister, E. B., & Zechmeister, J. S. (2003). Research methods in psychology (6th ed.). McGraw-Hill Higher Education.
Cita Chicago (17th ed.)Shaughnessy, John J., Eugene B. Zechmeister, i Jeanne S. Zechmeister. Research Methods in Psychology. 6th ed. Boston: McGraw-Hill Higher Education, 2003.
Cita MLA (9th ed.)Shaughnessy, John J., et al. Research Methods in Psychology. 6th ed. McGraw-Hill Higher Education, 2003.
Atenció: Aquestes cites poden no estar 100% correctes.