From Citizendium, the Citizens' Compendium
- Please sort and annotate in a user-friendly manner and consider archiving the URLs behind the links you provide. See also related web sources.
- Different Types of Maps Explained: Types of regular maps and also map substitutes: http://www.armystudyguide.com/content/army_board_study_guide_topics/land_navigation_map_reading/different-types-of-maps-e.shtml
- Basic Geodesy: http://earth-info.nga.mil/GandG/coordsys/geoarticles/pdfs/Article014_Projections_and_NGA_Products.pdf
- Google Maps API