United States Information Service. (1975). An outline of American geography. United States Information Agency.
Cita Chicago (17th ed.)United States Information Service. An Outline of American Geography. Nueva York: United States Information Agency, 1975.
Cita MLA (9th ed.)United States Information Service. An Outline of American Geography. United States Information Agency, 1975.
Atenció: Aquestes cites poden no estar 100% correctes.