Sitthisopasakul, Thittaya, Sirichai Kanjanawasee, and Teerana Bhongmakapat. 2021. “Social Returns on Investment for Doctor of Philosophy Program in Educational Measurement and Evaluation”. Kasetsart Journal of Social Sciences 42 (4):878-85. https://so04.tci-thaijo.org/index.php/kjss/article/view/255745.