1.
Khrueangwicha R, Nontapa R. Mathematical Concept Study the Ability to Use Symbols and Algebraic Operations that Affect Mathematical Problems in Fractions of 1st-Grade Students. IARJ [internet]. 2023 Nov. 26 [cited 2026 Oct. 11];3(6):221-38. available from: https://so03.tci-thaijo.org/index.php/IARJ/article/view/271254