Cheresharov, Stoyan, Hristo Hristov, Veneta Tabakova-Komsalova, and Veselina Naneva. “Hierarchical Learning Management System for the Insurance Industry”. International Journal of Emerging Technologies in Learning (iJET) 17, no. 21 (November 15, 2022): pp. 123–134. Accessed April 25, 2024. https://online-journals.org/index.php/i-jet/article/view/33595.