Koschmann, Albert Herbert  1896-1962 <br/><br/>
Principal gold-producing districts of the United States / 
by A. H. Koschmann and M. H. Bergendahl. 
 -- Washington :   United States Government Printing Office,   1968 
 - 283 p. -- 
 (Geological Survey Professional Paper  ; 610).
<br/><br/><label>Subjects--Topical Terms: </label><br/>Estados Unidos<br/>Oro - Producción<br/>Yacimientos de oro
<br/><br/><label>Universal Decimal Class. No.: </label>553.41(73) ; 669.213(73)