1. Kizel, V.A. and Burkov, V.I., Girotropiya kristallov (Gyrotropy of Crystals), Moscow: Nauka, 1980.
2. Mill, B.V. and Pisarevsky, Yu.V., Langasite-type materials: from discovery to present state, Proc. IEEE/EIA Int. Frequency Control Symp. and Exhibition, Kansas City, 2000, pp. 133–144.https://doi.org/10.1109/FREQ.2000.887343
3. Kaminskii, A.A., Mill’, B.V., and Sarkisov, S.E., Fizika i spektroskopiya lazernykh kristallov (Physics and Spectroscopy of Laser Crystals), Kaminskii, A.A., Ed., Moscow: Nauka, 1986.
4. Silvestrova, I.M., Pisarevskii, Yu.V., Mill’, B.V., and Kaminskii, A.A., Acoustic and electromechanical properties of piezoelectric crystals with the structure of trigonal Ca-gallogermanate, Dokl. Akad. Nauk, 1985, vol. 282, no. 3, pp. 575–578.
5. Kaldybaev, K.A., Konstantinova, A.F., and Perekalina, Z.B., Girotropiya odnoosnykh pogloshchayushchikh kristallov (Gyrotropy of Uniaxial Absorbing Crystals), Moscow: Inst. Sotsial’no-Ekonomicheskikh i Proizvodstvenno-Ekologicheskikh Problem Investirovaniya, 2000.