Parent Topic: PROJ
Snyder, John P., "Map Projections - A Working Manual", U.S.G.S. Professional Paper 1395, U.S. Geological Survey, Reston, Virginia, 1987.
"Software Documentation for GCTP, General Cartographic Transformation Package", U.S. Geological Survey, National Mapping Division, Reston, Virginia, 1990 (Unpublished).