1. Stress measurements at Elliot Lake;Coates;Bull. CIMM,1966
2. A comparison of two methods for measuring stress in rock;Van Heerden;Int. J. Rock Mech. Min. Sci.,1967
3. A note on the stress concentrations at the end of the cylindrical hole;Coates;Int. J. Rock Mech. Min. Sci.,1970
4. Bielenstein H. U., Gray W. M. and Udd J. File Data.
5. Tables of Normal Probability Functions;National Bureau of Standards,1955