Sari, Lisya, M. Adnan, and Hadiyanto Hadiyanto. “Enhancing Students’ Active Involvement, Motivation and Learning Outcomes on Mathematical Problem Using Problem-Based Learning”. International Journal of Educational Dynamics 1, no. 1 (February 19, 2019): 309-316. Accessed May 17, 2024. http://ijeds.ppj.unp.ac.id/index.php/IJEDS/article/view/70.