Creator
- National Atlas of the United States4
- Geological Survey (U.S.)3
- Arndt, Raymond E.2
- Bawiec, Walter J.2
- Beikman, Helen M.2
- King, Philip B.2
- Schruben, Paul G.2
- Stackhouse, Cecil2
- United States. Bureau of Transportation Statistics2
- Blackburn, Laura1
- Lannoo, Michael J.1
- Nanjappa, Priya1
- Patuxent Wildlife Research Center1