Santy, Lauti Dwita, and Hermes Panggabean. “The Potential of Ketungau and Silat Shales in Ketungau and Melawi Basins, West Kalimantan: For Oil Shale and Shale Gas Exploration”. Indonesian Journal on Geoscience, vol. 8, no. 1, Mar. 2013, pp. 39-53, doi:10.17014/ijog.8.1.39-53.