Thupthein P, Ugsonkid S, Chuntra C. The Study of Grade 11 Students’ Problem-Solving Ability on Sequences and Series by Using Teaching Through Problem Solving. IARJ [internet]. 2026 May 10 [cited 2026 Sep. 28];6(3):e291376. available from: https://so03.tci-thaijo.org/index.php/IARJ/article/view/291376