TY  - BOOK
AU  - Ridge, John Drew,
TI  - Ore deposits of the United States, 1933-67: the graton-sales volume 
PY  - 1968///
CY  - Metallurgical, and Petroleum Engineer,, New York
PB  - The American Institute of Mining
KW  - Ore deposits
KW  - united states
KW  - Mines and mineral resources
N1  - Includes bibliographical references
ER  -