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Bibliography/Links
Bilbiography:

Books:
Wilkes, Kenneth (2000);Ocean Navigator 7th ed, Adlard Coles Nautical ( London )

Websites:

          
Celestial Navigation Net, http://www.celestialnavigation.net/
          
Global Positioning History, http://www.bvoservices.com/gpshist.html
          
          
          
Traditional Celestial Navigation, http://www.ruf.rice.edu/~feegi/astro.html