Link

Roberds, W.J., Iwano, M., and Einstein, H.H. (1990). Probabilistic mapping of rock joint surfaces. In Rock Joints: proceedings of the International Symposium on Rock Joints (W. Barton, E. Stephansson, eds.), Loen, Norway, 4-6 June 1990, pp. 681-691. Balkema, Rotterdam, 814 pages. ISBN 9061911095