1. Barton, N. and Stephansson (1990): Rock Joint Review of Predictive Capabilities of JRC-JCS Model in Engineering Practice, Proc. Intrnl. Symp. On Rock Joint, Leon, Norway.
2. The shear strength of rock and rock joints
3. Bieniawski, Z.T. (1968): The Effect of Specimen Size on The Strength of Coal, International Journal on Rock Mechanics and Mining Sciences & Mecahnics Abstracts, V. 5 n. 4, 325–335.
4. Bieniawski, Z.T. (1973): Engineering Classification of Jointed Rock Masses, Trans. S. Afr. Inst. Civ. Eng. 15. pp. 335 – 344.
5. Bieniawski, Z.T. (1989): Engineering Rock Mass Classifications, John-Wiley, New York.