Roddy,Dennis <br/><br/>
Electronic communications 

 - 4th ed. 
 - New Delhi :  Pearson Prentice-Hall of India Pvt. Ltd.;  2008 
<br/><br/><label>ISBN: </label>9788177585582 
<br/><br/><label>Dewey Class. No.: </label>621.38  / ROD/E