"Pankaj tyagi" <br/><br/>
I discover  7(A text book for ICSE Physis) 

 - INDIA  Cambridge university Press  2012 
 - 114 
<br/><br/><label>ISBN: </label>9781107681279 
<br/><br/><label>Dewey Class. No.: </label>530  / L 1939