Admiralty list of radio signals volume 6, part 5 : pilot services, vessel traffic services and port operations: North America, Canada and Greenland. 
 -  The United Kingdom Hydrographic Office.  2013 
 - xx, 316 pages 
Radio in navigation.
M 623.89 Ad6 2013
                        Radio in navigation.
M 623.89 Ad6 2013