1. C.M. Wayman, JOM (June 1980), p. 129.
2. K. Kalima and Y. Sohama, J. Jpn. Soc. Powder Metall., 29 (1992), p. 127.
3. M. Igharo and J.V. Wood, Powder Metall, 28 (1985), p. 131.
4. T.W. Duerig, J. Albrecht and G.H. Gessinger, JOM (Dec. 1982), p. 14.
5. A.D. Bratchikov et al., Sov. Powd. Metall. Met. Ceram., 19 (1980), p. 5.