1. Clark, C.M. & Peterson, P.L. (1986). Teachers' thought processes . In M. C. Wittrock (Ed.), Handbook of research on teaching (3rd ed.) (pp. 255-296). New York: Macmillan.
2. Cronbach, L.J. (1966). The logic of experiments on discovery. In L. S. Shulman & E. R. Keislar (Eds.), Learning by discovery: A critical appraisal (p. 75-92). Chicago: Rand McNally .