(1978). Recent research concerning the development of spatial and geometric concepts. ERIC Clearinghouse for Science, Mathematics, and Environmental Education.
Chicago-Zitierstil (17. Ausg.)Recent Research Concerning the Development of Spatial and Geometric Concepts. Columbus, Ohio: ERIC Clearinghouse for Science, Mathematics, and Environmental Education, 1978.
MLA-Zitierstil (9. Ausg.)Recent Research Concerning the Development of Spatial and Geometric Concepts. ERIC Clearinghouse for Science, Mathematics, and Environmental Education, 1978.
Achtung: Diese Zitate sind unter Umständen nicht zu 100% korrekt.