1. K. Hauffe:Reaktionen in und an festen Stoffen, p. 880, Springer-Verlag, Berlin, 1966.
2. A. Bergholm:Trans. TMS-AIME, 1961, vol. 221, pp. 1121–27.
3. A. A. Chochran and P. W. Martin: U.S. Bur. Mines Rep. Invest, no. 5994, 1962.
4. R. R. Brown, F. E. Block, and A. W. Henderson: U.S. Bur. Mines Rep. Invest, no. 6402, 1964.
5. G. V. Seryakov, S. A. Vaks, V. V. Zheltova, and E. P. Strashun:Zh. Norg. Khim., 1967, vol. 12, pp. 8–14.