MOSTAFA, M. Compu Castel: An Instructional Tool for Teaching Firewall Concepts : "Analysis of Knowledge Retention". International Journal of Computer and Information Technology(2279-0764), [S. l.], v. 9, n. 1, 2020. DOI: 10.24203/ijcit.v9i1.2. Disponível em: https://ijcit.com/index.php/ijcit/article/view/2. Acesso em: 23 jan. 2022.