1. G. Goodman, G.H. Haertling, D.C. Hill, and H.L. Tuller: inCeramic Materials for Electronics, R.C. Buchanan, ed., Marcel Dekker, New York, NY, 1986, pp. 87, 164, and 236.
2. J. Harada:Landolt-Bornstein, K.H. Hellwege and A.M. Hellwege, eds., Group III, Springer-Verlag, Berlin, 1981, vol. 16a, pp. 66–67.
3. C. Kittel:Introduction to Solid State Physics, 6th ed., Wiley, New York, NY, 1986, ch. 13.
4. J.P. Bonsack:Ceram. Bull., 1970, vol. 50, pp. 488–92.
5. M. Kahn:J. Am. Ceram. Soc, 1971, vol. 54, pp. 455–57.