WAKHIDAH, Nur. HEMAT BERKOMUNIKASI DENGAN VOIP. Jurnal Transformatika, [S. l.], v. 5, n. 2, p. 83–91, 2008. DOI: 10.26623/transformatika.v5i2.25. Disponível em: https://journals.usm.ac.id/index.php/transformatika/article/view/25. Acesso em: 29 jun. 2026.