Ratna Wardani, B. S. R. “Critical Success Factors for E-Learning in Vocational Training: A Comparative Analysis Between ICT Experts, Trainer and Faculty”. International Journal of Advanced Science and Technology, Vol. 28, no. 16, Dec. 2019, pp. 720 -23, http://sersc.org/journals/index.php/IJAST/article/view/1945.