1. Discussion of G. Hocking's paper A method of distinguishing between single and double plane sliding of tetrahedral wedges;Cruden;Int. J. Rock Mech. Min. Sci. & Geomech. Abstr.,1978
2. Methods of Geological Engineering in Discontinuous Rocks;Goodman,1976
3. A method of distinguishing between single and double plane sliding of tetrahedral wedges;Hocking;Int. J. Rock Mech. Min. Sci. & Geomech. Abstr.,1976
4. Discussion of graphical stability analysis of slopes in jointed rock by John, K.W.;Panet,1969