Ley, Willy. <br/><br/>
The poles / 
by Willy Ley and the editors of Time-life books. 
 - 2nd ed. 
 - Hong Kong :  Time-Life Books,  1980. 
 - 192 p. ;  28 cm. 
 - Life Nature Library. .
<br/><br/>Bibliography : p.186. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Polan regions.