Julma, Kattaleya, and Metta Marwiang. “The Effectiveness of Multimedia Instructional Material on at Risk Student’s Achievement in Mathematics”. Journal of Education Khon Kaen University (Graduate Studies Research) 13, no. 3-4 (December 30, 2019): 1–8. Accessed May 5, 2024. https://so02.tci-thaijo.org/index.php/EDGKKUJ/article/view/242943.