Roddy, Dennis <br/><br/>
Electronic communications / 
Dennis Roddy, John Coolen 
 - 3rd ed. 
 - Reston, VA :  Reston Pub. Co.,  1984 
 - xii, 788 p. :  ill. ;  24 cm. 
<br/><br/> Includes index 
<br/><br/><label>ISBN: </label>0835915980 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Telecommunication