TY  - BOOK
AU  - Bownocker,J.A.
AU  - Campbell,Marius R.
TI  - The coal fields of the United States
T2  - U.S. Geological survey. Professional paper
AV  - QE75 .P9 no. 100
PY  - 1929///
CY  - Washington
PB  - U.S. Govt. print. off.
KW  - Coal
KW  - Ohio
KW  - United States
N1  - At head of title: Department of the interior; Issued also as House doc. no. 1806, 64th Cong., 2d sess
ER  -