1. P. Bakke, K. Pettersen, and H. Westengen, JOM 55, 46 (2003).
2. T. Du, Chin. J. Nonferrous Met. 6, 15 (1996).
3. J.S. Rao, H.J. Li, H.S. Xue, and J. Cent, South Univ. Technol. 17, 28 (2010).
4. H.M. Zhu, Rare Earth Metal Production by Molten Salt Electrolysis (New York: Springer, 2014), pp. 1765–1772.
5. Z.H. Chen, Adv. Mater. Ind. 6, 31 (2018).