1. On the stress distribution at the base of a stationary crack;Williams;Trans. ASME, J. Appl. Mech.,1957
2. Mathematical Theory of Elasticity;Sokolnikoff,1956
3. Bearing pressures and cracks;Westergaard;J. Appl. Mech.,1939
4. On the Westergaard method of crack analyses;Sih;J. Fracture Mech.,1966
5. On the modified Westergaard equations for certain plane crack problems;Eftis;J. Fracture Mech.,1972