Creator
- United States. Bureau of Transportation Statistics9
- United States. Bureau of the Census. Geography Division3
- United States. Federal Aviation Administration2
- Vanderbilt Engineering Center for Transportation Operations and Research2
- Waterborne Commerce Statistics Center (U.S.)2
- Environmental Systems Research Institute (Redlands, Calif.)1
- Gap Analysis Program (U.S.)1
- U.S. Census Bureau. Geography Division1
- United States. Federal Highway Administration1
- United States. Office of the Deputy Under Secretary of Defense (Installations and Environment)1