1. R. C. Garvie, R. H. J. Hannink andR. T. Pascoe,Nature 258 (1975) 703.
2. R. T. Pascoe andR. C. Garvie, ?Ceramic Microstructures 1976?, edited by R. M. Fulrath and J. A. Pask (Westview Press, Boulder, 1977).
3. R. C. Garvie, R. H. J. Hannink andC. Urbani, Proceedings of the 4th CIMTEC meeting, St Vincent, Italy, May (1979).
4. M. V. Swain, to be published.
5. M. Suezawa andS. Ishioka,Mat. Sci. Eng. 37 (1979) 282.