Fajri, Nur, and Asmaidi Asmaidi. “Application of Kumon Learning Model to Improve Student Learning Outcomes in Economic Math Subject”. Jurnal Inotera 5, no. 2 (July 13, 2020): 85-91. Accessed October 19, 2020. https://inotera.poltas.ac.id/index.php/inotera/article/view/106.