Maintaining the permissibility of electric cap lamps

Author:	Zellers, Donald Henry,
Additional Authors:	Hooker, A. B.
Year:	1935
Document Type:	USBI
Issuing Agency:	U.S. Dept. of the Interior, Bureau of Mines,
SUDOC:	I 28.27:6832
Series:	Information circular / United States Department of the Interior, Bureau of Mines ;
Report Number:	6832
Subjects:	Electricity in mining
	Electric lamps
Link:	https://hdl.handle.net/2027/mdp.39015077568833