1. R. S. Carmichael, CRC Handbook of Physical Properties of Rocks, Vol.3, CRC Press, Inc., Boca Raton (1984).
2. E. I. Il’nitskaya, R. I. Teder, E. S. Vatolin, et al., Properties of Rock and Methods of Their Determination [in Russian], Nedra, Moscow (1969).
3. T. Karman, “Festigkeitsversuche unter allseitigem druk mitt über forschungsarbeiten,” V. D. I. (1912).
4. M. M. Protod’yakonov, Ratings of Rock Strength and Methods of Their Determination [in Russian], Nauka, Moscow (1964).
5. J. D. Byerlee, “Friction of Rocks,” Pageoph.,615, 116 (1978).