Chumpoojan, S., and M. Thongmoon. “The Development of Mathematical Problem-Solving Ability by Using Deductive Learning With GeoGebra Program on Preliminary Data Analysis Topic for Matthayomsuksa 6 Students”. Journal of Roi Et Rajabhat University, vol. 15, no. 3, Dec. 2021, pp. 125-33, https://so03.tci-thaijo.org/index.php/reru/article/view/242683.