Magfiroh, Magfiroh, Sufyani Prabawanto, and Rizky Rosjanuardi. “Learning Obstacle of Students in Geometrical Sequence and Series”. KnE Social Sciences 9, no. 13 (April 26, 2024): 569–577. Accessed May 19, 2024. https://knepublishing.com/index.php/KnE-Social/article/view/15960.