Sianipar, Johannes Harungguan. “Pengembangan Sistem Informasi Penerbitan Buku Rohani HKBP Indonesia”. TRIDARMA: Pengabdian Kepada Masyarakat (PkM) 5, no. 1 (May 7, 2022): 151-163. Accessed July 25, 2026. https://iocscience.org/ejournal/index.php/abdimas/article/view/2282.