Abou El-Seoud, S., El-Sofany, H., Ghaleb, F., Daoud, S., AL Ja’am, J., & Hasna, A. (2007). XML and Databases for E-Learning Applications. International Journal of Emerging Technologies in Learning (iJET), 2(4). https://doi.org/10.3991/ijet.v2i4.190