1. A. S. Berezhnoi, in: Proc. 2nd Conference on Refractory Materials [in Russian], AN SSSR, Moscow-Leningrad (1941), pp. 58?65.
2. V. A. Ragozinnikov, I. L. Shchetnikova, E. I. Kelareva, et al., Ogneupory, No. 11, 25?29 (1966).
3. R. E. Vol'fson et al., Ogneupory, No. 4, 35?39 (1972).
4. Ya. V. Klyucharov and S. A. Suvorov, Ogneupory, No. 5, 42?50 (1967).
5. I. S. Kainarskii, N. V. Gul'ko, É. V. Degtyareva, et al., Ogneupory, No. 1, 37?42 (1968).