1. Krasnenko, T.I., Zolotukhina, L.V., and Andrianova, L.V., Russ. J. Inorg. Chem., 2000, vol. 45, no. 3, p. 323.
2. Krasnenko, T.I., Zolotukhina, L.V., and Andrianova, L.V., Neorgan. Mater., 2000, vol. 35, no. 10, p. 1226.
3. Calvo, C., Canad. J. Chem., 1973, no. 51, p. 1004.
4. Krasnenko, T.I., Zubkov, V.G., Tyutyunnik, A.P., et al., Kristallografiya, 2002, vol. 48, no. 1, p. 35.
5. Drown, I.I. and Hummel, F.A., Trans. Brit. Ceram. Soc., 1961, vol. 64, no. 8, p. 387.