Burchard, Ernest F. <br/><br/>
The production of fluorspar in 1913 with a note on cryolite. 

 - Washington, D.C.  Government Printing Office  1914 
 - pp .373-381 
 - Mineral Resources of the United States, calendar year 1913-Part II .
<br/><br/> Impreso 
<br/><br/> La producción de fluorita en 1913 con una nota en la criolita. 
<br/><br/><br/>Ingles 
<br/><br/><label>Subjects--Topical Terms: </label><br/>MINERIA<br/>FLUORITA<br/>CRIOLITA
<br/><br/><label>Subjects--Index Terms: </label>PRODUCCION DE FLUORITA 
<br/><br/><label>Dewey Class. No.: </label>549.4