Shelford, Victor E.  1877-. <br/><br/>
The ecology of North America 
by Victor E. Shelford 
 - Urbana  University of Illinois Press  1963 
 - xxii,610 p.  : ill., maps.,  ; 26 cm. 
<br/><br/><label>ISBN: </label>0252723899 
<br/><br/><label>LCCN: </label>63-007255 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Ecology--North America