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3. A. S. Tetelman andA. J. Mcevily, “Fracture of Structural Materials” (John Wiley and Sons Inc, New York, 1967).
4. F. A. McClintock,Proc. Roy. Soc. 285 (1965) 58.
5. F. A. McClintock, S. M. Kaplan, andC. A. Berg Jr,Internat. J. Fracture Mech. 2 (1966) 614.