TY  - BOOK
AU  - Kerr, George L.,
TI  - Elementary coal-mining: Designed to meet the requirements of students attending classes on coal-mining, and of miners and others engaged in practical work 
AV  - TN802 K47
PY  - 1902///
CY  - London
PB  - C. Griffin
KW  - Minas de carbón
ER  -