Hazard of firing open, unconfined shots in coal mines

Author:	Ankeny, M. J.
Year:	1952
Document Type:	USBI
Issuing Agency:	U.S. Dept. of the Interior, Bureau of Mines,
SUDOC:	I 28.27:7632
Series:	Information circular / United States. Bureau of Mines ;
Report Number:	7632
Subjects:	Mine explosions
	Coal mines and mining
Link:	https://hdl.handle.net/2027/mdp.39015078455915