1. Recent experiences with the Q System in tunnel support design;Barton,1976
2. Unsupported ground openings;Barton,1976
3. Session report on rock mass classifications;Barton,1976
4. Engineering classification of rock masses for the design of tunnel support;Barton;Rock Mech.,1974
5. Rock mass investigation in depth. Reliability of different methods for drill hole investigations;Bergman,1974