Nursasongko, A., Mariani, S., & Dwijanto, D. (2020). The Ability of Problem-Solving for Eighth Grade Student on Cooperative Problem Solving Learning Assisted by GeoGebra 3D. Unnes Journal of Mathematics Education Research, 9(2), 123-130. Retrieved from https://journal.unnes.ac.id/sju/ujmer/article/view/32815