5Blumenfeld P C. etal( 1991 ). Motivating project - based learning:sustaining the doing, supporting the learning. Educational Psychologists,26(3&4), 369 - 398.
6Harden R. M. &Davis, M.H. (1998) . The continuum of problem - based learning. Medical Teacher, Vol. 20, Iseae4, p317 - 342.
7Dolmans D. Etal(1997). Seven principles of effective case design for a problem-based curriculum. Medical Teacher, Vol. 19, Issue 3,p185 - 194.
8Gailagher S. A. &Stepien W, Jr (1995) . Implementing problem -based learning in science classrooms. Scholl Science & Mathematics,Vol. 95, Issue 3. p136 - 144.
9Schunk D.H. & Zimmerman B.J. (1994) Self- regulation of learning and performance. Lawrence Erlbaum Associates, Publishers. p8.
10Schunk D.H. & Zimmerman B.J. (1998) .Serf-regulated learning: From teaching to self - reflective practice. The Guilford Press.
