Lumban Gaol, Nasib Tua, Tresia Ronestyka Sitinjak, and Johanes Waldes Hasugian. “Efektivitas Kepemimpinan Kepala Sekolah Kristen Di Masa Pandemi Covid-19”. Regula Fidei : Jurnal Pendidikan Agama Kristen 6, no. 2 (October 4, 2021): 81–96. Accessed February 20, 2026. https://www.christianeducation.id/e-journal/index.php/regulafidei/article/view/89.