Smith, Philip S. <br/><br/>
Sulphur and pyrites in 1919. 

 - Washington, D.C.  Government Printing Office  1922 
 - pp. 535-546 
 - Mineral Resources of the United States, 1919-Part II .
<br/><br/> Impreso 
<br/><br/><br/>Ingles 
<br/><br/><label>Subjects--Topical Terms: </label><br/>MINERIA<br/>AZUFRE<br/>PIRITA
<br/><br/><label>Dewey Class. No.: </label>553