Marlinda S, Effendi KNS. Students’ Epistemological Obstacle in Solving Problems on the Subject of Quadratic Equations. Radian [Internet]. 2024 Aug. 30 [cited 2026 Apr. 2];2(4):151-65. Available from: https://journal-fkip.unsika.ac.id/index.php/radian/article/view/12091