Defi Yanti Hulu, Leni Marlina Laia, Defi Susanti Duha. DEVELOPMENT OF THE OPPORTUNITY MODULE TO IMPROVE HIGH SCHOOL LEVEL UNDERSTANDING ABILITY OF MATHEMATICAL CONCEPTS. Afore [Internet]. 2023Feb.25 [cited 2025Sep.12];2(1):26 -36. Available from: https://jurnal.uniraya.ac.id/index.php/Afore/article/view/764