Design and development of drill equipment

Author:	Hadden, J. D.
Additional Authors:	Cervik, Joseph,
Year:	1969
Document Type:	TPRM
Issuing Agency:	U.S. Dept. of the Interior, Bureau of Mines ;
SUDOC:	I 28.26/6:11
Series:	Technical progress report ;
Report Number:	11
Subjects:	Coal mines and mining
	Mine ventilation
	Boring machinery
Link:	https://hdl.handle.net/2027/mdp.39015077584079