(1994). Map adventures / U.S. Department of the Interior, U.S. Geological Survey.
Cita Chicago (17th ed.)Map Adventures / U.S. Department of the Interior, U.S. Geological Survey. 1994.
Cita MLA (9th ed.)Map Adventures / U.S. Department of the Interior, U.S. Geological Survey. 1994.
Atenció: Aquestes cites poden no estar 100% correctes.