Safety evaluations of longwall roof supports

Author:	Barczak, Thomas M.
Year:	1989
Document Type:	USBI
Issuing Agency:	U.S. Dept. of the Interior, Bureau of Mines,
SUDOC:	I 28.27:9221
Series:	Information circular / Bureau of Mines ;
Report Number:	9221
Subjects:	Longwall mining
	Mine roof control--Evaluation
Link:	https://hdl.handle.net/2027/mdp.39015078457556