Keen, Martin L. <br/><br/>
The how and why wonder book of prehistoric mammals / 
Martin L. Keen ; illustrated by John Hull, ed. Donald D. Wolf 
 - New York :  Grosset & Dunlap,  [1962] 
 - 48 p. :  ill.(chiefly col.) ;  28 cm. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Paleontology--Juvenile literature
<br/><br/><label>Dewey Class. No.: </label>560