Htet Htike Htwe and Kay Thi Lwin, Study on Extraction of Niobium Oxide from Columbite–Tantalite Concentrate. journal = {International Journal of Chemical and Molecular Engineering}, [online]. World Academy of Science, Engineering and Technology. October 2008, vol. 22(10). 235 - 237 [viewed 18 September 2024]. Available from: https://publications.waset.org/pdf/11665.