ค่อมบุญ ป.; ภิรมจิตรผ่อง เ. A Development of Mathematics Problem Solving Skills Using Problem-Based Learning Plan for Prathom Suksa 2 Students in Schools under the Office of Ubon Ratchathani Primary Education Service Area 2 . Ubon Ratchathani Journal of Research and Evaluation, [S. l.], v. 4, n. 2, p. 23–30, 2021. Disponível em: https://so06.tci-thaijo.org/index.php/ubonreseva/article/view/250983. Acesso em: 3 oct. 2026.