Aresta, R. M., E. W. Pratomo, V. Geraldino, J. D. Santoso, and S. Mulyatun. “IMPLEMENTASI MULTI ENKRIPSI ROT 13 PADA SYMBOL WHATSAPP”. Journal of Information System Management (JOISM), vol. 2, no. 1, July 2020, pp. 1-5, doi:10.24076/joism.2020v2i1.158.