จินตะกัน อ. “IMPROVING COMPANY WORK SAFETY WITH 3E PRINCIPLES AND INCREASE QUALITY OF CLOCK IN CLOCK OUT SYSTEM OF THE COMPANY : A CASE STUDY OF THE COMPANY A”. Journal of KMITL Business School, vol. 10, no. 1, Apr. 2020, pp. 1-13, https://so02.tci-thaijo.org/index.php/fam/article/view/239940.