Factors governing the selection of the proper level interval in underground mines

Author:	Vanderburg, William O.
Year:	1932
Document Type:	USBI
Issuing Agency:	U.S. Dept. of Commerce, Bureau of Mines,
SUDOC:	C 22.11:6613
Series:	Information circular / Bureau of Mines ;
Report Number:	6613
Subjects:	Mines and mineral resources--Cost of operation
	Mining engineering
Link:	https://hdl.handle.net/2027/mdp.39015086485441