TY  - BOOK
AU  - Jackson,ChasF
AU  - J.H.Hedges
TI  - Metal-Mining Practice: Bullutin 419
PY  - 1939///
CY  - Washington
PB  - United States Government Printing Office
KW  - Mining engineering
KW  - Technologies of explosives
KW  - United States
N1  - includes index, consolidates and analyzes information on mining methods
ER  -