Creator
- United States. Bureau of Transportation Statistics9
- National Atlas of the United States4
- Geological Survey (U.S.)3
- United States. Federal Aviation Administration2
- United States. Federal Transit Administration2
- Vanderbilt Engineering Center for Transportation Operations and Research2
- Waterborne Commerce Statistics Center (U.S.)2
- Environmental Systems Research Institute (Redlands, Calif.)1
- Institute for Water Resources (U.S.). Navigation Data Center1
- Strocko, Ed1
- United States. Federal Highway Administration1