Chookhampaeng, A. P. D. C., and K. Chadong. “Professional Learning Community Applying in Cooperative Learning to Enhance Working Group Process of Mathayomsueksa 1 Thakhonyang Pittayakom School Maha Sarakham Province”. Journal of Research and Development Institute Rajabhat Maha Sarakham University, vol. 5, no. 2, Dec. 2018, pp. 13-24, https://so03.tci-thaijo.org/index.php/rdirmu/article/view/210450.