1. Underground excavations in rock;Hoek,1980
2. Strength variation and deformational behavior in anisotropic rock;Donath,1964
3. Fracture of anisotropic rock;Hoek;J S Afr Inst Min Metall,1964
4. The mechanical behaviour of anisotropic sedimentary rocks;McLamore;ASME J Eng Ind,1967
5. Horino FG, Ellickson ML. A method of estimating strength of rock containing planes of weakness. Report of investigation 7449, US Bureau of Mines, 1970.