Welsh, Jeffrey H. <br/><br/>
Computerized, remote monitoring systems for undergroud coal mines 
Welsh, Jeffrey H. 
 - Washington  Bureau of mines  1982 
<br/><br/><label>Subjects--Topical Terms: </label><br/>MINERIA<br/>PROGRAMA DE COMPUTADORA
<br/><br/><label>Universal Decimal Class. No.: </label>004.42