1. G.N. Zviadadze, I.N. Karyazina, A.A. Petrov, Yu.B. Makarov, L.I. Blokhina, and Yu.I. Mel’nik: Izv. Akad. Nauk SSSR, Met., 1981, vol. 1, pp. 11–17 (in Russian); Chemical Abstract, American Chemical Society, Columbus, Ohio, 1981, vol. 94, Abstract No. 195573k.
2. P. Li, D. Tang, and Q. Shen: Zhongguo Xitu Xuebao, 1984, vol. 2, pp. 38–45 (in Chinese); Chemical Abstract, American Chemical Society, Columbus, Ohio, 1985, vol. 103, Abstract No. 218791a.
3. K.A. Gschneidner, Jr., N. Kippenhan, and O. Dale McMasters: Thermochemistry of the Rare Earths, IS-RIC-6, Rare-Earth Information Center, Iowa State University, Ames, IA, 1973.
4. R.A. Sharma and R.N. Seefurth: J. Electrochem. Soc., 1988, vol. 135, pp. 66–71.
5. F. Seon: Fr. Demande FR 2,555,611 (Cl. C22C28/00), May 31, 1985, Appl. 83/18,888, 25, Nov. 1983, p. 18; Chemical Abstract, American Chemical Society, Columbus, Ohio, 1984, vol. 104, Abstract No. 37563c.