Panichsuay, W. ., and S. . Waiboonya. “The Lessons of Training Mathematical Processing Skills for Elementary Students’ Competencies”. Journal of Education Studies, vol. 49, no. 1, Mar. 2021, p. EDUCU4901017 (16 pages) doi: 10.14456/educu.2021.17, https://so02.tci-thaijo.org/index.php/EDUCU/article/view/248205.