Suspension roof support.

Author:	Thomas, Edward.
Additional Authors:	Metcalfe, Arthur., Barry, A. J.
Year:	1949
Document Type:	USBI
Issuing Agency:	U.S. Dept. of the Interior, Bureau of Mines,
SUDOC:	I 28.27:7533
Series:	Information circular / United States Department of the Interior, Bureau of Mines ;
Report Number:	7533
Subjects:	Mine roof bolting
	Mine roof control
Link:	https://hdl.handle.net/2027/mdp.39015078463851