1. Engineering classification of rock masses for the design of tunnel supports;Barton;Rock Mechanics,1974
2. Engineering classification of jointed rock masses;Bieniawski;Trans. S. Afr. Instn. civ. Engrs.,1974
3. Rock failure and tunnel supports loading;Daemen,1972
4. Geomechanical evaluation of tunnel stability underground rock conditions in a Himalayan tunnel;Dube,1979
5. Untersuchrugeh Zur Erkenntris des Gebirgsdruck;Fenner;Glükauf,1938