Simandl, George J., Richard O. Burt, David L. Trueman, and Suzanne Paradis. 2018. “Economic Geology Models 4. Tantalum and Niobium: Deposits, Resources, Exploration Methods and Market – A Primer for Geoscientists”. Geoscience Canada 45 (2):85-96. https://doi.org/10.12789/geocanj.2018.45.135.