1. Fischbeck, K., and Dorner, O., Z. Anorg. Chem., 181, 377 (1929).
2. Pfeil, L. B., J. Iron and Steel Inst., 119, 501 (1929); 123, 237 (1931).
3. Wagner, C., Z. phys. Chem., 22, 199, 212 (1933); 25, 71, 209 (1934); 40, 455 (1951). Also “Atom Movements” (Amer. Soc. Met.), 153 (1951).
4. Mott, N. F., Trans. Farad. Soc., 35, 1175 (1939); 36, 472 (1940); 43, 429 (1947).
5. Groesbeck, E. C., and Waldron, L. J., Proc. Amer. Soc. Test. Mat., 31, ii, 286 (1931).