Abduh, M., S. Waluya, and Scolastika Mariani. “Analysis of Problem Solving on IDEAL Problem Solving Learning Based on Van Hiele Theory Assisted by Geogebra on Geometry”. Unnes Journal of Mathematics Education Research 9, no. 2 (December 23, 2020): 170-178. Accessed December 22, 2024. https://journal.unnes.ac.id/sju/ujmer/article/view/33198.