1. Metals, alloys and compounds-high purities do make a difference!
2. Extractive metallurgy of rare earths
3. Y. Shindo, H. Miyazaki, Proc. Fall Meeting of MMIJ (Mining and Materials Processing Institute of Japan), Sapporo, 1992, p. 46.
4. I. Barin, Thermochemical Data of Pure Substances, VCH, Weinheim, 1989.
5. T.B. Massalski (Ed.), Binary Alloy Phase Diagrams, American Society for Metals, Metals Park, OH, 1990.