United Kingdom Hydrographic Office <br/><br/>
Admiralty list of Radio Signals Vol:4 

 - 1st 
 -  United Kingdom hydrographic O  2009 
<br/><br/> YES 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Marine engineering Marine 
<br/><br/><label>Dewey Class. No.: </label>