TY  - BOOK
AU  - Singer,D.A.
AU  - Chaffee,Maurice A.
TI  - Grade and tonnage relationships among copper deposits
T2  - Geological Survey professional paper
U1  - 553.430973 
PY  - 1975///
CY  - Washington
PB  - United States Government Printing Office
KW  - Copper ores
KW  - United States
KW  - Copper
KW  - Analysis
KW  - Geochemical prospecting
N1  - Includes bibliographie
ER  -