1. Yu. M. Kartashev and A. A. Grokhol'skii, Operating Instructions for Determining the Compressive Strength of Rocks [in Russian], VNIMI, Leningrad (1973).
2. E. I. Il'nitskaya, Properties of Rocks and Methods of Determining Them [in Russian], Nedra, Moscow (1969).
3. G. N. Kuznetsov, Mechanical Properties of Rocks [in Russian], Ugletekhizdat, Moscow (1947).
4. L. S. Burshtein, Static and Dynamic Tests of Rocks [in Russian], Nedra, Leningrad (1970).
5. B. Paul, ?Macroscopic criteria of plastic flow and brittle fracture,? in: Fracture [Russian translation], Vol. 2, Mir, Moscow (1975).