1. G. T. Hahn, M. Sarrate, and A. R. Rosenfield:Proc. A.F. Conf. on Fatigue and Fracture ofAircraft Struct’s. and Mater., AFFDLTR-70-144, September 1970, p. 425.
2. R. M. Pelloux:Proc. A.F. Conf. on Fatigue and Fracture of Aircraft Struct’s. and Mali’s., AFFDL-TR-70-144, September 1970, p. 409.
3. J. R. Rice:Amer. Soc. Test. Mater., Spec. Tech. Publ. 415, 1967, p. 247.
4. J. R. Rice and M. A. Johnson:Inelastic Behavior of Solids, M. F. Kanninen,et al, eds., p. 641, McGraw-Hill, New York, 1970.
5. M. Klesnil and P. Lukas:Fracture 1969, P. L. Pratt,et al, eds., p. 725, Chapman and Hall, London, 1969.