TODOROVA, K. Modeling and design of learning content management systems: UML as a tool for learning system design. Ann. Sofia Univ. Fac. Math. and Inf., [S. l.], v. 98, p. 231–242, 2008. Disponível em: https://ftl5.uni-sofia.bg/index.php/fmi/article/view/140. Acesso em: 4 dec. 2024.