Pisapak, J. and Thipkong, S. (2009) “The Development of Mathematics Ability in Solving Problems for Prathomsuksa 2 Students at Kasetsart University Laboratory School by Using Polya’s Problem Solving Process”, Kasetsart Journal of Social Sciences, 30(1), pp. 1–9. available at: https://so04.tci-thaijo.org/index.php/kjss/article/view/246479 (accessed: 13 October 2026).