Interactions between multiple seam longwall and room-and-pillar operations : a case study in Boone County, WV / by Gregory J. Chekan and Rudy J. Matetic (Report of investigations ; 9299)
Interactions between multiple seam longwall and room-and-pillar operations : a case study in Boone County, WV / by Gregory J. Chekan and Rudy J. Matetic