Permana, Sulaksana, Shiva Frida Vincia, Anggita Amilia, Ahmad Maksum, Kurnia Setiawan Widana, and Johny Wahyuadi Soedarsono. 2018. “Enrichment on Bangka Tin slag’s Tantalum and Niobium Oxide Contents through Non-Fluoride Process”. Eastern-European Journal of Enterprise Technologies 5 (12 (95):56-64. https://doi.org/10.15587/1729-4061.2018.129914.