Kaemkaeng, Aroonroj, and Nuttawut Rojniruttikul. “Factors Affecting Communication Competency of Operative Employees at Union Plastic Public Company Limited”. Journal of Liberal Arts and Management Science Kasetsart University 6, no. 2 (December 31, 2019): 82–90. accessed April 8, 2025. https://so14.tci-thaijo.org/index.php/jlams/article/view/58.