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2. T. HAKKARAINEN, D. Tech thesis, Helsinki University of Technology (1971).
3. D. E. LAUGHLIN and J. W. CAHN,Metall. Trans. 5 (1974) 972.
4. J. A. CORNIE, A. DATTA and W. A. SOFFA, ibid.4 (1973) 727.
5. R. WAGNER, in Proceedings of the 5th International Conference on the Strength of Metals and Alloys, Aachen, August 1979, edited by P. Haasen, V. Gerold and G. Kostorz (Pergamon Press, New York, 1980) Vol. 1, p. 645.