Symmetric Cryptosystem Based on Petri Net. JOURNAL OF UNIVERSITY OF BABYLON for Pure and Applied Sciences, [S. l.], v. 26, n. 1, p. 1–8, 2017. DOI: 10.29196/jub.v26i1.347. Disponível em: https://www.journalofbabylon.com/index.php/JUBPAS/article/view/347. Acesso em: 4 may. 2025.