TY  - BOOK
AU  - Cassidy,Samuel M.
ED  - American Institute of Mining, Metallurgical, and Petroleum Engineers.
TI  - Elements of practical coal mining
AV  - TN802 E45
PY  - 1973///
CY  - New York, New York
PB  - American Institute of Mining, Metallurgical, and Petroleum Engineers, Society of Mining Engineers
KW  - Huella
KW  - Minas y mineria
ER  -