Abd El-Hakeem, Shereen. “E-Learning As a Prerequisite of 21st Century Skills and Training of Mathematics Teachers.”. International Journal of research in Educational Sciences. 4, no. 2 (March 15, 2021): 131 - 154. Accessed May 7, 2024. https://www.iafh.net/index.php/IJRES/article/view/277.