Keefer, William R.  1924- <br/><br/>
The Geologic Story of Yellowstone National Park / 
By William R. Keefer ; Illustrated by John R. Stacy. 
 -- Washington :   United States Government Printing Office,   [1972?] 
 - 92 p.  il. -- 
 (Geological Survey Bulletin  ; 1347).
<br/><br/> Fecha real de registro 15-05-1972 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Geologia - Parque nacional de Yellowstone
<br/><br/><label>Universal Decimal Class. No.: </label>551.7(7 Yellowstone)