Reddy T Yellamanda  & Yellamanda T Reddy Gh Sankara <br/><br/>
Principles of Agronomy .-5 th edn .-978-93-272-6915-4 

 - 5 th edn  
 -  Kalyani Publishers, New Delhi, New Delhi  2016 
<br/><br/><label>ISBN: </label>978-93-272-6915-4 
<br/><br/><label>Dewey Class. No.: </label>J:1   P16/B28052