Cita APA (7th ed.)
(1989). Washington DC: A Traveler's Guide to the District of Columbia and Nearby Attractions. National Park Service, Division of Publications.
Cita Chicago (17th ed.)
Washington DC: A Traveler's Guide to the District of Columbia and Nearby Attractions. National Park Service, Division of Publications, 1989.
Cita MLA (9th ed.)
Washington DC: A Traveler's Guide to the District of Columbia and Nearby Attractions. National Park Service, Division of Publications, 1989.
Atenció: Aquestes cites poden no estar 100% correctes.