4Evenson D,Hmelo C.Introduction to problem based learning: gaining insights on learning interactions through multiple methods of enquiry [A].Evenson D,Hmelo C.Problem Based Learning: A Research Perspective on Learning Interactions [C].Mahwah: Lawrence Erlbaum,2000:1-18.
5Glaser, R.The reemergence of learning theory within instructional research [J].American Psychologist, 1990, 45(1):29-39.