- United States. Bureau of Transportation Statistics25
- National Atlas of the United States13
- Geological Survey (U.S.)6
- Thomas, William G., 1964-6
- Hunt, Raquel4
- Environmental Systems Research Institute (Redlands, Calif.)3
- United States. Federal Highway Administration3
- Waterborne Commerce Statistics Center (U.S.)3
- Institute for Water Resources (U.S.). Navigation Data Center2
- Strocko, Ed2
- United States. Federal Aviation Administration2
- United States. Federal Transit Administration2
- Vanderbilt Engineering Center for Transportation Operations and Research2
- Battelle Memorial Institute1
- Beningo, Steve1
- Blades, Doug1
- Canada Centre for Remote Sensing1
- Carey, Mathew, 1760-18391
- Colton, J. H. (Joseph Hutchins), 1800-18931
- Firestine, Theresa1
