Barnal,J.D <br/><br/>
Vigyan ki samajik bhumika 

 - Delhi  Granth shilpi prakashan  2000 
 - 1-606p. 
<br/><br/><label>ISBN: </label>81-86684-38-7 
<br/><br/><label>Dewey Class. No.: </label>303.483    Bar.P