Varia Juita, Mersiana. “Analisis Sistem Pengendalian Internal Dalam Optimalisasi Sistem Pembelian Pada PT. Mulia Safety Service Surabaya”. Ascarya: Journal of Islamic Science, Culture, and Social Studies 1, no. 2 (September 13, 2021): 204–216. Accessed October 6, 2026. https://journal.ascarya.or.id/index.php/iscs/article/view/88.