Distance Education in Transition
Peters, O. (2002) Distance Education in Transition Oldenburg, Germany: Biblioteksund informationssystem der Universität Oldenburg
Freedom to Learn
Rogers, C. (1969) Freedom to Learn Columbus, OH: Charles E. Merrill Publishing Co.
The construction of social reality
Searle, J. (1996) The construction of social reality. New York: Simon & Shuster
Contingencies of Reinforcement
Skinner, B. (1969) Contingencies of Reinforcement New York: Appleton-Century- Crofts
Learner-Centered Teaching
Weimer, M. (2002) Learner-Centered Teaching San Francisco: Jossey-Bass.