8Van Merrienboer, J. J.G. ,Kirschner,P. A. ,Kester,L.. Tak- ing the load of a learners' mind: Instructional design for complex learning[-J]. Educational Psychologist,2003, 38(1) :5-13.
9D. Klahr,M. Nigam. The Equivalence of Learning Paths in ear- ly Science Instruction[J]. Psychol. Sci. , 2004,15 (10) : 661 - 667.