6D N Perkins, "Technology Meets Constructivism : Do They Make a Marriage? " [J]. Educational Technology, may , 1991.
7Yong-Chil Yang, Wee-Kyo Chin, " Motivational Analyses on the Effect of Type of Instructional Control on Learning from Computer-Based Instruction"[J].Education Technology Systems Vol. 25 (1) . 1996-1997.