Buku Ajar Teologi Sistematika 2: Doktrin Makhluk Rohani (Malaikat Dan Iblis). Yayasan Yuta Pendidikan Cerdas, 2025. Accessed July 27, 2026. https://publisher.yayasanyutapendidikancerdas.com/index.php/yutapress/catalog/book/32.