Snyder, John P., "Map Projections--A Working Manual", U.S. Geological Survey
Professional Paper 1395 (Supersedes USGS Bulletin 1532),
United State Government Printing Office, Washington D.C., 1987.
Snyder, John P. and Voxland, Philip M., "An Album of Map Projections",
U.S. Geological Survey Professional Paper 1453 ,
United State Government Printing Office, Washington D.C., 1989.
"Cartographic Projection Procedures for the UNIX Environment-
A User's Manual" by Gerald I. Evenden,
USGS Open File Report 90-284and Release 4 Interim Reports (2003)
Snyder, John P., "Flattening the Earth -
Two Thousand Years of Map Projections", Univ. Chicago Press, 1993
"New Equal-Area Map Projections for Noncircular Regions", John P. Snyder,
The American Cartographer, Vol 15, No. 4, October 1988, pp. 341-355.
Snyder, John P., "Map Projections--A Working Manual", U.S. Geological
Survey Professional Paper 1395 (Supersedes USGS Bulletin 1532), United
State Government Printing Office, Washington D.C., 1987.
"Software Documentation for GCTP General Cartographic Transformation
Package", U.S. Geological Survey National Mapping Division, May 1982.
