Mangal, S.K. <br/><br/>
Essentials of educational technology / 
S.K. Mangal, Uma Mangal 
 - Delhi :  PHL Learning,  2013 
 - 812 p. 
<br/><br/><label>ISBN: </label>9788120337237 
<br/><br/><label>Dewey Class. No.: </label>371.33 MAN U