Samart, C., Intanam , N. ., & Rattanaraj, P. . (2022). Development of a Social Skill Test for the 9th Grade Students in the Schools under Ubon Ratchatani Primary Educational Service Area by Using Polytomous Item Response Theory. Journal of Graduate School, Pitchayatat, Ubon Ratchathani Rajabhat University, 17(1), 77–88. Retrieved from https://so02.tci-thaijo.org/index.php/Pitchayatat/article/view/252009