1. Extractive metallurgy of rare earths
2. Rare earths supply chains: Current status, constraints and opportunities
3. Castor, S. B.; Hedrick, J. B. Rare Earth Elements (Industrial Minerals Volume, 7th ed.; Littleton, Colorado: Society for Mining, Metallurgy, and Exploration, 2006; pp. 769–792.
4. Cordier, D. J.; Hedrick, J. B. Rare Earths; Reston, U.S.: U.S. Department of the Interior and U.S. Geological Survey, 2010; Vol. 1.
5. Rare Earth Elements;Lusty P.;Nat. Environ. Res. Counc.; Br. Geolog. Survey,2010