K. . Borotoding, M. . Limbong, and H. . Tampubolon, “Pengaruh Kepemimpinan Kepala Sekolah terhadap Mutu Pendidikan di SMK Kristen Bittuang (The Influence of Principal Leadership on the Quality of Education at Bittuang Christian Vocational School)”, jptam, vol. 5, no. 1, pp. 1–6, Jun. 2021.