References
- Beth, E. W.; Piaget, J., Mathematical Epistemology and Psychology (translated from French by W, Mays), D. Reidel Publishing Company, Dordrecht-Holland; Gordon and Breach Science Publishers, New York, 1966,
- Flavell, J. H., The Developmental Psychology of Jean Piaget, Van Nostrand Company, Inc., Princeton, New Jersey, 1963.
- Hildreth, G. H.; Griffiths, N. L,; McGauvran, M. E., “Metropolitan Readiness Tests, Form A,”, Harcourt Brace and World, Inc., New York, 1965.
- Piaget, J., The Child’s Conception of Number, Routledge and Kegan Paul Ltd., London, England, 1952.
- Piaget, J., Psychology of Intelligence, Littlefield, Adams and Co., Totowa, New Jersey, 1966.
- Sigel, I. E.; Hooper, F. H (eds.), Logical Thinking in Children, Holt, Rinehart, and Winston, Inc., New York, 1968.