The American Practical Navigator, Nathaniel Bowditch, National Imagery and Mapping Agency, 2002

ftp://ftp.flaterco.com/xtide/Bowditch.pdf

Admiralty Manual of Navigation

http://navlib.net/wp-content/uploads/2013/10/admiralty-manual-of-navigation-vol-1-1964-english501c.pdf

https://archive.org/details/manualofnavigati00grea