Das Asha <br/><br/>
Grah vigiyan: Patthya pushtak aur prayogatmak pushtak 

 - New Delhi, India  Arya Book Depot  1995 
 - xiii,84p. 
<br/><br/><br/>Gyarahvi kaksha ke liye 
<br/><br/><label>ISBN: </label>81-7063-189-0 
<br/><br/><label>Source: </label>Textual