RODDY, Dennis. <br/><br/>
Electonic communications. 

 - 3rd edi. 
 - Virginia.  Prentice/Hall international I  nc.        1984 
 - xii, 788p. 
<br/><br/><label>ISBN: </label>0 13 250440 5 
<br/><br/><label>Dewey Class. No.: </label>621.38