ILHAM, M.; PURNAMASARI, S. D. Sistem Informasi Layanan Surat Internal Dan Eksternal Berbasis Web. Journal of Information Technology Ampera, [S. l.], v. 2, n. 3, p. 150–166, 2021. DOI: 10.51519/journalita.volume2.isssue3.year2021.page150-166. Disponível em: https://journal-computing.org/index.php/journal-ita/article/view/94. Acesso em: 23 may. 2022.