Babbie, E. (1986). Observing ourselves: Essays in social research. Prospect Heights, IL: Waveland.

Brookfield, S. D. (1987). Developing critical thinkers. San Francisco, CA: Jossey-Bass.

Diestler, S. (2001). Becoming a critical thinker (3rd ed.). Upper Saddle River, NJ: Prentice-Hall.

Kimmell, A. J. (1996). Ethical issues in behavioral research: A survey. Malden, MA: Blackwell Publishers