A study of falls of roof and coal in Northern Colorado

Author:	Tomlinson, Herbert.
Year:	1933
Document Type:	BMRA
Issuing Agency:	U.S. Dept. of Commerce, Bureau of Mines,
SUDOC:	C 22.12:3199
Series:	Report of investigations / United States Department of Commerce, Bureau of Mines ;
Report Number:	3199
Subjects:	Mine roof control
	Mine accidents--Colorado
	Mine timbering
Link:	https://hdl.handle.net/2027/mdp.39015077562968