6[1]Spiro,R.J.& Jehng,J.(1990).Cognitive Flexibility and Hypertext:Theory and Technology for the Nonlinear and Multidimensional Traversal of Complex Subject Matter.In D.Nix & R.J.Spiro (Eds.).Cognition,Education,and Multimedia:Exploring ideas in high technology.163-205.
7[2]Spiro,R.J.,Feltovich,P.J.,Jacobson,M.J.and Coulson,R.L.Cognitive Flexibility,Constructivism,and Hypertext:Random Access Instruction for Advanced Knowledge Acquisition in Illstructured domains.Educational Technology.1991,May,24-33
