von Glasersfeld, E. (1990). "An exposition of constructivism: Why some like it radical". Journal for Research In Mathematics Education – Monograph. 4: 19–29 & 195–210 [22]. doi:10.2307/749910. ISSN0883-9530. JSTOR749910. (p. 22).
Hsueh, Y (2009). "Piaget in the United States, 1925–1971. In U. Müller, J. I. M. Carpendale & L. Smith (Eds.), The Cambridge Companion to Piaget (pp. 344–370). Cambridge, UK: Cambridge University Press. Müller, U., Burman, J. T., & Hutchinson, S. (2013). The developmental psychology of Jean Piaget: A quinquagenary retrospective". Journal of Applied Developmental Psychology. 34 (1): 52-55. doi:10.1016/j.appdev.2012.10.001. ISSN0193-3973.
von Glasersfeld, E. (1990). "An exposition of constructivism: Why some like it radical". Journal for Research In Mathematics Education – Monograph. 4: 19–29 & 195–210 [22]. doi:10.2307/749910. ISSN0883-9530. JSTOR749910. (p. 22).
von Glasersfeld, E. (1990). "An exposition of constructivism: Why some like it radical". Journal for Research In Mathematics Education – Monograph. 4: 19–29 & 195–210 [22]. doi:10.2307/749910. ISSN0883-9530. JSTOR749910. (p. 22).
Hsueh, Y (2009). "Piaget in the United States, 1925–1971. In U. Müller, J. I. M. Carpendale & L. Smith (Eds.), The Cambridge Companion to Piaget (pp. 344–370). Cambridge, UK: Cambridge University Press. Müller, U., Burman, J. T., & Hutchinson, S. (2013). The developmental psychology of Jean Piaget: A quinquagenary retrospective". Journal of Applied Developmental Psychology. 34 (1): 52-55. doi:10.1016/j.appdev.2012.10.001. ISSN0193-3973.