Advanced geostatistics in the mining industry :proceedings of the NATO Advanced Study Institute held at the Istituto di Geologia Applicata of the University of Rome, Italy, 13-25 October 1975 : edited by M. Guarascio, M. David, C. Huijbregts. - Guarascio, M.,; David, Michel.; Huijbregts, Ch. J. (D. Reidel Pub. Co.,, 1976)