Roddy,Dennis <br/><br/>
Electronic communications / 
Roddy,Dennis. 
 - 4th ed. 
 - Delhi:  Pearson Education,  2003. 
 - ix,820p;25cm 
<br/><br/>Includes bibliographical references. 
<br/><br/><label>ISBN: </label>8129701065 
<br/><br/><label>Dewey Class. No.: </label>621.3822 ROD