1. Some new Q value correlations to assist in site characterisation and tunnel design;Barton;Int J Rock Mech Min Sci,2002
2. Determining rock mass deformability;Bieniawski;Int J Rock Mech Min Sci Geomech Abstr,1978
3. Application of the Q-system in design decisions concerning dimensions and appropriate support for underground installations;Barton;Int Conf Subsurface Space, Rockstore, Stockholm, Subsurface Space,1980
4. Serafim JL, Pereira JP. Considerations on the geomechanical classification of Bieniawski. In: Proceedings of the Symposium on Engineering Geology and Underground Openings, Lisboa, Portugal, 1983. p. 1133–44.
5. A nonlinear deformation modulus based on rock mass classification;Nicholson;Int J Min Geol Eng,1990