Keen, R <br/><br/>
Wireless direction finding 
Roland Keen 
 - 4th ed. 
 - London  Jliffe & Sons  1949 
 - xii, 1059p. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Astronomy and Astrophysics Thesaurus<br/>Wireless
<br/><br/><label>Universal Decimal Class. No.: </label>621.3  / KEE