Spatial Algorithm Web Sites
- http://geospatialmethods.org/spheres/
- http://planetmath.org/encyclopedia/AreaOfASphericalTriangle.html
- PgAstro includes PgSphere, has Area on a Shere calculation, http://www.pgastro.org/doc/html/index.html
- http://trs-new.jpl.nasa.gov/dspace/handle/2014/40409?mode=full&submit_simple=Show+full+item+record Area on a sphere algorithm
