Office of Planning, Environment, & Realty (HEP)
Bureau of the Census, 1990, "TIGER/Line Census Files: machine readable data files" prepared by the Bureau of the Census.
National Ocean Service, 1992, "National Ocean Service D Scale Digital Shoreline, Release 1.0", US Department of Commerce, National Oceanic and Atmospheric Administration, Rockville MD 20852.
Peterson, Bruce 1992, "Description of the National Highway Planning Network V1.1", Center for Transportation Analysis, Oak Ridge National Laboratory, Oak Ridge TN.
Snyder, John P., 1987, "Map Projections - A Working Manual," US Geological Survey Professional Paper 1395, United States, Government Printing Office, Washington, DC.
US Geological Survey, 1989, "Digital Line Graphs From 1:100,000 Scale Maps", US Department of the Interior US Geological Survey, Reston VA.