Gupta ,s.p <br/><br/>
sankhiki ke siddhant 

 - New delhi  Sultan Chand and sons  2008 
 - 576p 
<br/><br/><label>ISBN: </label>81-8054-457-5 
<br/><br/><label>Dewey Class. No.: </label>519-5H              gup.P8