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

 - 1st /   2001. 
 - New Delhi:  S. Chand & Co. Ltd.,  2001. 
 - 264p. 
<br/><br/><label>Subjects--Personal Names: </label><br/>Botany, Ecology. 
<br/><br/><label>Dewey Class. No.: </label>574.5