1. Crystals with the Fluorite Structure. Electronic, Vibrational, and Defect Properties, Hayes, W., Ed., Oxford: Clarendon, 1974.
2. Sobolev, B.P., The Rare Earth Trifluorides, part 1: The High Temperature Chemistry of the Rare Earth Trifluorides, Barcelona: Inst. d’Estudis Catalans, 2000.
3. Yushkin, N.P., Volkova, N.V., and Markova, G.A., Opticheskii flyuorit (Optical Fluorite), Moscow: Nauka, 1983.
4. Zverev, V.A., Krivopustova, E.V., and Tochilina, T.V., Opticheskie materialy. Uchebnoe posobie dlya konstruktorov opticheskikh sistem i priborov (Optical Materials: A Learning Guide for Designers of Optical Systems and Instruments), St. Petersburg: ITMO, 2013, part 2.
5. Kaminskii, A.A., Laser Crystals: Their Physics and Properties, New York: Springer, 1990.