A comparison of borer, ripper, and conventional mining products in Illinois No. 6 seam coal

Author:	Schmidt, Robert L.
Additional Authors:	Engelmann, William H., Fumanti, R. R.
Year:	1972
Document Type:	BMRA
Issuing Agency:	U.S. Dept. of Interior, Bureau of Mines,
SUDOC:	I 28.23:7687
Series:	Report of investigations / United States Department of the Interior, Bureau of Mines ;
Report Number:	7687
Subjects:	Coal-handling
	Coal--Illinois--Analysis
	Mining engineering--Illinois
Link:	https://hdl.handle.net/2027/mdp.39015078520536