1. Standard method of test for plane strain fracture toughness in metallic materials;ASTM;ASTM E399-81,1981
2. Fracture propagation in rock;Ingraffea,1985
3. Assessment of experimental techniques applicable to rock fracture,1986
4. Suggested methods for determining fracture toughness of rock;Ouchterlony;Int. Soc. Rock Mech. Comm. Testing Methods,1988
5. A simplified method for measuring plane strain fracture toughness;Barker;Engng Fracture Mech.,1977