1. D. Broek, Elementary Engineering Fracture Mechanics, Noordhoff International Publishing, Leyden, The Netherlands (1974).
2. N.E. Frost, K.J. Marsh and L.P. Pook, Metal Fatigue, Clarendon Press, Oxford (1974).
3. R.W. Hertzberg, Deformation and Fracture Mechanics of Engineering Materials, Wiley, New York (1976).
4. S.T. Rolfe and J.M. Barsom, Fracture and Fatigue Control in Structures, Prentice-Hall, Englewood Cliffs, New Jersey (1977).
5. D.V. Nelson, Experimental Mech., Feb. 1977.