TY  - RPRT
TI  - Application of grade and tonnage deposit models; the search for ore deposits possibly amenable to small-scale mining
AU  - J. D. Bliss
AU  - G. E. McKelvey
AU  - M. S. Allen
PY  - 1990
DO  - 10.3133/ofr90412
UR  - https://pubs.usgs.gov/publication/ofr90412
ID  - ofr90412
ER  -