Smith, Sydney F. <br/><br/>
Telephony and telegraphy :  an introduction to telephone and teegraph instruments and exchanges / 
by Sydney F. Smith 
 - Glasgow :  Oxford University Press,  c1969 
 - 285 p. ;  25 cm. 
<br/><br/> Includes index 
<br/><br/><label>ISBN: </label> PND 4.95 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Telephone<br/>Telegraph
<br/><br/><label>Dewey Class. No.: </label>621.385