TY  - BOOK
ED  - United States.
TI  - Hours and earnings in anthracite and bituminous coal mining
AV  - HD8051 .A62 no. 316
PY  - 1922///
CY  - Washington
PB  - Govt. print. off.
KW  - Hours of labor
KW  - United States
KW  - Wages
KW  - Coal miners
KW  - Coal mines and mining
ER  -