1. Shevyakov, A.M., Kuznetsova, G.N., and Aleskovskii, V.B., Trudy 2 Vsesoyuznogo Soveshchaniya po Khimii Okislov pri Vysokikh Temperaturakh (Proc. 2nd All-Union Conf. on Chemistry of Oxides at High Temperatures), Leningrad, 1967, p. 149.
2. Kol’tsov, S.I., Zh. Prikl. Khim., 1969, vol. 52, no. 5, p. 1023.
3. Damyanov, D., Velikova, M., Ivanov, Iv., and Vlaev, L., J. Non-Crystal Solids, 1988, vol. 105, no. 1, p. 107.
4. Lakomaa, E.-L., Haukka, S., and Suntola, T., Applied Surface Science, 1992, vols. 60–61, p. 742.
5. Haukka, S., Lakomaa, E.-L., and Root, A., J. Phys. Chem., 1993, vol. 97, no. 19, p. 5085.