Amadi, Dwi Nor, Arief Budiman, and Pradityo Utomo. “Analysis of the Effectiveness of VPN and PPTP Protocol in E-Link Health Report Application Using NDLC Method”. Journal of Information Systems and Informatics 6, no. 2 (June 13, 2024): 949–958. Accessed March 7, 2026. https://journal-isi.org/index.php/isi/article/view/746.