Siallagan, Thomson, and Heryanto Heryanto. “Peran Etika Kristen Dalam Dunia Pendidikan Modern Bagi Guru Di Yayasan Methodist Berastagi”. Jurnal Pengabdian Masyarakat Bangsa 4, no. 6 (August 10, 2026): 2843–2851. Accessed August 10, 2026. https://jurnalpengabdianmasyarakatbangsa.com/index.php/jpmba/article/view/4859.