BPB <br/><br/>
Build your own Intercoms 

 - 1st 
 -  "BPB,New Delhi"  1980 
<br/><br/> TRANSFERED 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Telephone Electronics 
<br/><br/><label>Dewey Class. No.: </label>