1. Wilks, J. Ind. Diam. Rev. 382 (1973).
2. Ikawa, N. & Tanaka, T. Ann. C.I.R.P. 19, 153 (1971); Bull. Jap. Soc. prec. Engng, 7, 97 (1973).
3. Vishnevskii, A. S. & Lysenko, A. V. Sint. Almazy 4, 11 (1974).
4. Vishnevskii, A. S., Lysenko, A. V., Ositinskaya, T. D. & Delevi, V. G. Nauk SSR, Neorganich. Mater. 11, 1589 (1975).
5. Komanduri, R. & Shaw, M. C. Nature 255, 211 (1975).