The GS50 projection provides a conformal projection suitable only for maps of the 50 United States. Scale varies less than 2% throughout the area covered. Distortion is very low as well. It is not a standard projection in the sense that it uses complex polynomials (of the tenth order) rather than a trigonometric formulation, though it was developed from an oblique stereographic projection.
- Snyder, John Parr (1985). "Computer-assisted map projection research" (Abstract + pdf (74Mb)). Bulletin (United States Geological Survey) 1629: 79–92; 147–51. Retrieved 26 March 2013.
- Snyder, John Parr (1987). "Map Projections: A Working Manual" (Abstract + pdf (22Mb)). Professional Paper (United States Geological Survey) 1395: 203–212. Retrieved 26 March 2013.