Verma, P.S. <br/><br/>
Principles of ecology (environmental biology) 

 - 2nd ed. 
 - New Delhi  S.Chand  1985 
 - viii, 591 p. 
<br/><br/><label>ISBN: </label>245834 
<br/><br/><label>Dewey Class. No.: </label>591.5  / VER