Boericke, William F., <br/><br/>
Prospecting and operating small gold placers / 
By William f. boericke 
 - 2 
 - xi, 145 páginas 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Minas de oro
<br/><br/><label>LC Class. No.: </label>TN421  / B65 1966