Zimmermann, W., & Cunningham, S. (1991). Visualization in teaching and learning mathematics. The Mathematical Association of America.
Chicago-viite (17. p.)Zimmermann, Walter, ja Steve Cunningham. Visualization in Teaching and Learning Mathematics. Washington, D.C: The Mathematical Association of America, 1991.
MLA-viite (9. p.)Zimmermann, Walter, ja Steve Cunningham. Visualization in Teaching and Learning Mathematics. The Mathematical Association of America, 1991.
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