König, Claus. <br/><br/>
Owls of the world / 
by Claus König, Friedhelm Weick. 
 - 2nd ed. 
 - London :  Christopher Helm,  c2008. 
 - 528 p. :  ill., col ;  25 cm. 
 - Helm identification guides .
 - Helm identification guides .
<br/><br/> Includes bibliographical references and index. 
<br/><br/><label>ISBN: </label>9780713665482 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Owls.