พวงสมบัติก., เสนารัตน์ส. and เสนารัตน์เ. (2018) “Development of the Testing and Diagnostic Assessment Program of Problem Solving Skills in Application of Linear Equation”, Ubon Ratchathani Journal of Research and Evaluation, 7(2), pp. 90-100. Available at: https://www.tci-thaijo.org/index.php/ubonreseva/article/view/143189 (Accessed: 22October2019).