TY  - RPRT
TI  - National Mineral-Resource Assessment: The 1996 estimate of undiscovered gold, silver, copper, lead, and zinc remaining in the United States
AU  - Joseph A. Briskey
AU  - Paul G. Schruben
PY  - 1997
DO  - 10.3133/70220355
UR  - https://pubs.usgs.gov/publication/70220355
ID  - 70220355
ER  -