NGUYEN, V. L.; PHAN, P. L. Some Evaluations on Open Soure E-learning Systems. Journal of Technical Education Science, [S. l.], v. 4, n. 1, p. 123–127, 2009. Disponível em: https://www.jte.edu.vn/index.php/jte/article/view/944. Acesso em: 7 apr. 2026.