Langley, Graham <br/><br/>
Telecommunications primer 
Graham Langley 
 - London  Pitman  1983 
 - viii, 148 p.  ill.  25cm 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Telecommunication systems
<br/><br/><label>Dewey Class. No.: </label>621.38