Ratih Kusuma Ningtias, et al. “Shadow Education in the Era of Industrial Revolution 4.0 It’s Disruptive Impact on Islamic Religious Education Institutions in Indonesia”. Madinah: Jurnal Studi Islam, vol. 13, no. 1, May 2026, pp. 120-34, https://doi.org/10.58518/madinah.v13i1.4809.