Singh, A. L. <br/><br/>
Nitrogen fixation in Indian rice fields (Azolla and Blue green Algae) 

 - Bikaner  Agro Botanical  1989 
 - 236p. 
<br/><br/><label>ISBN: </label> RS 200.00 
<br/><br/><label>Source: </label> RS 200.00 
<br/><br/><label>Dewey Class. No.: </label>633.188940954 SIN