1. Anisotropy of a schistose gneiss;Delkotz,1966
2. Experimental study of shear failure in anisotropic rocks;Donath;Bull. Geol. Soc. Am.,1961
3. Methods and results from testing of rocks for road construction;Svenska Väginstitutet;Medd. No. 8,1928
4. Strength anisotropy of rocks;Aagaard,1976
5. The point-load strength test;Broch;Int. J. Rock Mech. Min. Sci.,1972