Tower's T.D.  _ <br/><br/>
Towers' international transistor selector: specification data for the identification..... 

 - 4th ed. 
 - Delhi  BPB  1992 
 - 432 p.  HB  24cm. 
<br/><br/><label>Dewey Class. No.: </label>621.381528,  / D, tow