1. American Psychological Association. (2002). Ethical principles of psychologists and code of conduct. American Psychologist, 57(12), 1060–1073.
2. Andrews, G., & Halford, G. S. (2002). A cognitive complexity metric applied to cognitive development. Cognitive Psychology, 45, 153–219.
3. Bidell, T. R., & Fisher, K. W. (1992). Beyond the stage debate: Action, structure, and variability in Piagetian theory and research. In R. J. Sternberg & C. A. Berg (Eds.), Intellectual development. New York, NY: Cambridge University Press.
4. Bigler, R. S., & Liben, L. (1992). Cognitive mechanisms in children’s gender stereotyping: Theoretical and educational implications of a cognitive-based intervention. Child Development, 63, 1351–1363.
5. Blackburn, J. A., & Papalia, D. E. (1992). The study of adult cognition from a Piagetian perspective. In R. J. Sternberg & C. A. Berg (Eds.), Intellectual development. New York, NY: Cambridge University Press.