แสงเพชร พีรพันธ์. “The Guidelines of Self Improvement for Employees to Be Professionals and Create Competitive Adventage of Electrical Indiusty in Rayong Province”. Journal of Industrial Business Administration 1, no. 2 (December 26, 2019): 69–81. Accessed May 3, 2024. https://so03.tci-thaijo.org/index.php/iba/article/view/232158.