Zin, N. A. M. ., and M. S. Mahmud. “Perceptions of Malaysian University Mathematics Instructors of the Challenges They Face in Implementing Effective Distance Learning”. International Journal of Learning, Teaching and Educational Research, vol. 23, no. 5, May 2024, pp. 158-79, http://www.ijlter.net/index.php/ijlter/article/view/1944.