Verma, P.S., <br/><br/>
Concept of Ecology 

 - 1st /   1999. 
 - Delhi:  S. Chand & Company Ltd.,  1999. 
 - 264p: 
<br/><br/><label>Subjects--Personal Names: </label><br/>Zoology, Ecology. 
<br/><br/><label>Dewey Class. No.: </label>574.5