Hassan, Prof. Esam Edris Kamtor Al. “The Effect of E- Program Based on Flipped Learning on Academic Achievement for Basic Eighth Grade Students in Khartoum State and Their Attitudes towards It.”. IJRDO- Journal of Educational Research 5, no. 6 (July 1, 2020): 01-11. Accessed May 18, 2024. https://ijrdo.org/index.php/er/article/view/3680.