Sands, Paul F. <br/><br/>
Blind pneumatic stowing in voids in abandoned mines / 
by P.F. Sands, C.M.K. Boldt, and T.M. Ruff. 
 - Washington, D.C. :  U.S. Dept. of the Interior, Bureau of Mines,  1990. 
 - 13 p. :  ill. 
 - Information circular ;  9268 .
 - Information circular (United States. Bureau of Mines) ;  9268. .
<br/><br/><label>LCCN: </label>90001809  
<br/><br/><label>Subjects--Topical Terms: </label><br/>Mine filling.<br/>Compressed air.<br/>Abandoned coal mines.