TY  - RPRT
TI  - Copper
AU  - Waldemar Lindgren
AU  - F.B. Weeks
AU  - V. C. Heikes
PY  - 1908
DO  - 10.3133/b340b
UR  - https://pubs.usgs.gov/publication/b340B
ID  - b340B
ER  -