Biswas, Nripendra N. <br/><br/>
Princples of Telephony 

 - Bombay  Asia Publishing  1970 
 - 144 p.  
<br/><br/> Includes index 
<br/><br/><label>ISBN: </label>0-210-22312-X 
<br/><br/><label>Dewey Class. No.: </label>TBB D66,48 L0;14