TY  - BOOK
AU  - Bertoldi, Michael J.
CN  - TN23
CN  - TN23
CY  - [Washington] :
DA  - 1977.
ID  - 10355
KW  - Strip mining
KW  - Coal mines and mining
KW  - Coal-mining machinery.
PB  - Dept. of the Interior,
PP  - [Washington] :
PY  - 1977.
T1  - Preliminary economics of mining a thick coal seam by dragline, shovel-truck, and scraper mining systems /
TI  - Preliminary economics of mining a thick coal seam by dragline, shovel-truck, and scraper mining systems /
VL  - 8761
ER  -