Effects of Ancient Stream Channel Deposits on Mine Roof Stability: A Case Study

Author:	Ingram, David K.
Year:	1987
Document Type:	N/A
SUDOC:	I 28.23:9092
Series:	United States Bureau of Mines Reports
Report Number:	R. I. 9092
Subjects:	Mine roof control.
	River channels -- Pennsylvania -- Pittsburgh Region.
Link:	http://digital.library.unt.edu/ark:/67531/metadc38733/