Langley, Graham. <br/><br/>
Telecommunications primer / 
Graham Langley. 
 - 2nd ed. 
 - London :  Pitman,  1986 
 - vi, 170 p. :  ill. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Telecommunication.
<br/><br/><label>LC Class. No.: </label>TK5101  / .L3165 1985 
<br/><br/><label>Dewey Class. No.: </label>384�19