1. S. Prochazka, in Proceedings of the Conference on Ceramics for High Performance Applications, Hyannis, Mass., November 1973, edited by J. J. Burke, A. E. Gorum, and R. N. Katz (Brook Hill Publishing Co., Chestnut Hill, Mass., 1975) p. 239.
2. K. H. Jack andW. I. Wilson,Nat. Phys. Sci. 238 (1972) 28.
3. I. B. Cutler, P. D. Miller, W. Rafaniello, H. K. Park, D. P. Thompson andK. H. Jack,Nature 275 (1978) 434.
4. A. Zangvil andR. Ruh, Paper presented at the 82nd Annual Meeting of the American Ceramic Society, Chicago, Ill., April, 1980.
5. M. Ish-Shalom, Paper presented at the Fall Meeting, Basic Science Division of American Ceramic Society, San Francisco, Ca., October, 1980.