History


Help on query formulation
Van Hiele Levels of Geometric Thought Revisited. Nochmals: die Van Hiele-Ebenen des geometrischen Denkens. (English)
Math. Teacher. (Mar 1991) v. 84(3) p. 210-21. [ISSN 0025-5769]
Valid XHTML 1.0 Transitional Valid CSS!