1. Recent advances in high-temperature niobium alloys
2. Tolley, R. J. Advances in Tantalum and Niobium Technology, Tantalum, 1992, Niobium International Study Center 69.
3. Angelelli, V. Yacimientos Metaliferos de la RepUblica Argentina I, Comisiem de Investigaciones Cientificas de la Provincia de Buenos Aires, 1984, pp. 203–205, 314-322.
4. A New process for the separation of tantalum from niobium