Verma, P. S <br/><br/>
Environmental biology : principles of ecology 
Verma, P. S Agarwal v.k. 
 - RAM NAGAR,  S. CHAND & COMPANY LTD.  1983 
 - viii,591 p  pc  23 
<br/><br/><label>ISBN: </label>8121908590 
<br/><br/><label>Dewey Class. No.: </label>570