Optimalisasi dan Produktivitas Alat Gali-Muat dan Alat Angkut pada Tambang Batu Granit PT Vitrama Properti di Desa Air Mesu, Kecamatan Pangkalan Baru, Kabupaten Bangka Tengah: Optimization and Productivity of Excavator and Dump Truck in Granite Mining Activity of PT Vitrama Properti at Air Mesu Village, Pangkalan Baru Subdistrict, Central Bangka Regency. (2020). MINERAL, 2(1), 8-15. https://doi.org/10.33019/mineral.v2i1.1541