JASSIM, J.N.; MUHSEN, H. J. One Algorithm to Cipher Messages in Columnar and Fixed Period-d Transposition Cipher. Ibn AL-Haitham Journal For Pure and Applied Sciences, Baghdad, Iraq., v. 22, n. 2, 2017. Disponível em: https://jih.uobaghdad.edu.iq/index.php/j/article/view/1231. Acesso em: 14 mar. 2025.