1. An article which reviews such reactions is by Taylor, J. Amer. Ceram. Soc., 17, 155 (1934).
2. Day and Allen, Carnegie Inst., Washington, Pub. No. 31.
3. Jander and Petri, Z. Elektrochem., 44, 747 (1938).
4. Michel-Levy and Wyart, C.R. Acad. Sci., Paris, 206, 261 (1938); 208, 1030 and 1594 (1939); 210, 733 (1940); 212, 89 (1941); Bull. Soc. franc. Miner., 70, 164 and 168 (1947); Mem. Soc. Geol. France, 26, No. 55 (1947). Discussions of Farad. Soc., No. 5, 323 (1949).
5. Doelter, “Mineralchemie”, 1, 601 (Steinkopf, 1912).