1. Beyond the third dimension;Banchoff,1990
2. A generalization of Piaget's logical-mathematical model for the stage of formal operations;Bart;Journal of Mathematical Psychology,1971
3. Structure and direction in thinking;Berlyne,1965
4. Bower, G. H. (1975). Cognitive psychology: An introduction. In: W. K. Estes, Handbook of learning and cognitive processes: vol. 1. Introduction to concepts and issues. New York: Wiley.
5. Bruner, J. S. (Ed.). (1966). Studies in cognitive growth. New York: Wiley.