1. B. P. Sobolev, The Rare Earth Trifluorides, Part 1: The High Temperature Chemistry of the Rare Earth Trifluorides (Institute of Crystallography, Moscow, Russia; Institut d′Estudis Catalans, Barcelona, Spain; 2000). www.books.google.ru/books/rare earth trifluorides
2. B. P. Sobolev, Crystallogr. Rep. 64, 713 (2019). https://doi.org/10.1134/S1063774519050183
3. L. R. Batsanova, Usp. Khim. 40, 945 (1971).
4. Ch. 45;O. Greis,1982
5. B. P. Sobolev, The Rare Earth Trifluorides, Part II: Introduction to Materials Science of Multicomponent Metal Fluoride Crystals (Institute of Crystallography, Moscow, Russia; Institut d′Estudis Catalans, Barcelona, Spain; 2001).