Rahmawati, Mutia, Sari, Siska, Triyoga, Alan, AND wati, Idar. " Characteristics of Coal and Cleat Attributes in Ulak Lebar and Surroundings Area, Lahat Regency, South Sumatra" Journal of Geoscience, Engineering, Environment, and Technology [Online], Volume 3 Number 2 (1 June 2018)