Dyfyniad APA

National Geographic Society (U.S.). Special Publications Division & Melham, T. (1989). Great American journeys. The Society.

Dyfyniad Arddull Chicago

National Geographic Society (U.S.). Special Publications Division and Tom Melham. Great American Journeys. Washington, D.C: The Society, 1989.

Dyfyniad MLA

National Geographic Society (U.S.). Special Publications Division and Tom Melham. Great American Journeys. The Society, 1989.

Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.