Syafardi, Heri, et al. “TARIFF POLICY AND DIGITAL GOVERNANCE IN COAL-SECTOR NON-TAX REVENUE: A SYSTEMATIC LITERATURE REVIEW ON FISCAL OPTIMIZATION”. Jurnal Ilmiah Ilmu Terapan Universitas Jambi, vol. 10, no. 1, Feb. 2026, pp. 422-37, doi:10.22437/jiituj.v10i1.53431.