Sharma, P.D, <br/><br/>
Ecology and Environment  Textual Documents 
By P.D. Sharma 
 - 7th ed. 
 -  Rastogi Piblications  1999 
 - pg 660:  23cm. 
<br/><br/><label>ISBN: </label>81-7133-420-2 
<br/><br/><label>Subjects--Index Terms: </label>Zoology Ecology G- Zoology 
<br/><br/><label>Dewey Class. No.: </label>591.5