1. K. Katayama, T. Watanabe, K. Matoba and N. Katoh, SAE Technical Paper Series 861 128 (1986).
2. K. Matoba, K. Katayama, M. Kawamura and T. Mizuno, SAE Technical Paper Series 880 702 (1988).
3. G. R. Terwilliger and F. F. Lange, J. Amer. Ceram. Soc.
57 (1974) 25.
4. D. Richerson, Amer. Ceram. Soc. Bull.
52 (1973) 560.
5. R. Becker and F. Thummler, in “Energy and Ceramics”, edited by P. Vincenzini (Elsevier, Amsterdam, 1980) p. 610.