Longer-than-seam-height drill development program

Author:	Derby, G. K.
Additional Authors:	Bevan, John E.,
Year:	1978
Document Type:	BMRA
Issuing Agency:	Dept. of the Interior, Bureau of Mines,
SUDOC:	I 28.23:8273
Series:	Report of investigations / Bureau of Mines ;
Report Number:	8273
Subjects:	Mine roof bolting
	Boring
Link:	https://hdl.handle.net/2027/mdp.39015078482802