Roddy, Dennis,   1931- <br/><br/>
Electronic communications /  [Book]. 
Dennis Roddy, John Coolen. 
 - 3rd ed. 
 - Virginia :   Reston publishing Company Inc.,   1984. 
 - xii, 788 p. :   ill. ;   24 cm. 
<br/><br/> Includes index. 
<br/><br/><label>ISBN: </label>0835915980 
<br/><br/><label>LCCN: </label>84003460 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Telecommunication.