Creator
- United States. Bureau of Transportation Statistics4
- Gap Analysis Program (U.S.)3
- National Atlas of the United States3
- Geological Survey (U.S.)2
- United States. Bureau of the Census. Geography Division2
- Institute for Water Resources (U.S.). Navigation Data Center1
- John A. Volpe National Transportation Systems Center (U.S.)1
- Miller, David1
- Rukstales, Kenneth S. (compiler)1