| Authors | Title | Year | |
|---|---|---|---|
| Mark, C; Esterhuizen, GS | 
                  Safety during the recovery of coal pillars under deep cover in the United States of America Deep Mining 2010: Proceedings of the Fifth International Seminar on Deep and High Stress Mining, Deep Mining 2010  | 
                  2010 | 
                  	
                  	
                  	
                  		 
                  	
                  	
                  	
                  	
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