D. Mildan, M. Johan, H. Z. Hakim, E. K. Army, and A. I. Mauladika, “ESTIMATE COAL RESOURCES IN BLOCK 3 KEBAN SOUTH SUMATERA USING USGS CIRCULAR 891”, Program Studi S1 Teknik Pertambangan Universitas Papua, vol. 9, no. 1, pp. 8–15, May 2026.