1. The J integral as a fracture criterion;Begley;ASTM STP,1972
2. The effect of specimen geometry on JIc;Landes;ASTM STP,1972
3. Some information from load deflection curves, useful in fracture toughness testing;Östensson;Engng Fracture Mech.,1974
4. A new method to find the point of onset of stable crack growth in fracture toughness tests;Mahlén,1975
5. An electrical impedance method for determination of crack growth;Öberg,1975