มะหาทอง แ, พรประไพ ศ. Mathematical Learning Activities on the Topic of Fraction by Using the Multigrade Classroom Learning Activities in the Primary Education level. Pitchayatat [internet]. 2019 Oct. 16 [cited 2025 Apr. 28];14(1):7-12. available from: https://so02.tci-thaijo.org/index.php/Pitchayatat/article/view/221551