1. K. A. Gschneidner, J. Alloys Compd. 193, 1 (1993).
2. G. G. Devyatykh and G. S. Burkhanov, High-Purity Refractory and Rare-Earth Metals (Nauka, Moscow, 1993; Int. Sci. Publ., Cambridge, 1997).
3. O. D. Chistyakov, G. S. Burkhanov, N. B. Kol’chugina, and N. N. Panov, Vysokochist. V-va 3, 57 (1994).
4. N. B. Kol’chugina, ‘‘Physicochemical foundations and practical aspects of the purification of rare earth metals and the creation of highly efficient hard magnetic materials R–Fe–B (R = Nd, Pr, Tb, Dy),’’ Doctoral (Eng.) Dissertation (Moscow, 2018).
5. V. B. Chzhan, ‘‘Study of the structure and magnetocaloric properties of gadolinium, terbium, dysprosium after hydrogenation and Laves’ rare earth phases,’’ Cand. Sci. (Phys.-Math.) Dissertation (Moscow, 2017).