Hickok, William Orville,  1905- <br/><br/>
The minerals of Pennsylvania: Iron ores of Pennsylvania, 
by William O. Hickok, IV. 
 - Harrisburg, Pa.,  Department of Internal Affairs, Topographic and Geologic Survey,  1939. 
 - 21 p. incl. tables.  23 cm. 
 - Bulletin M,  18-B .
<br/><br/> At head of title: Pennsylvania Geological survey, Fourth series  With Ashley, G. H. The undeveloped mineral resources of Pennsylvania. 1933. (Bulletin M18-A) 
<br/><br/>Bibliographical footnotes. 
<br/><br/><label>LCCN: </label>gs 40000142  
<br/><br/><label>Subjects--Topical Terms: </label><br/>Iron ores--Pennsylvania.
<br/><br/><label>LC Class. No.: </label>TN24.P4  / A7