BUREAU OF MINES <br/><br/>
MINERAL FACTS AND PROBLEMS 

 - 0 
 - U.S.A.  UNITED STATES DEPARTAMENT  1970 
 - 1291 pag.  27 cm 
 - 0  0 .
<br/><br/>MINERAL INDUSTRIES-NONMETALLIC 
<br/><br/><label>Subjects--Topical Terms: </label><br/>CIENCIAS PURAS
<br/><br/><label>Dewey Class. No.: </label>549  / B94