Dyfyniad APA

National Geographic Society (U.S.). Special Publications Division. (1983). Preserving America's past. The Society.

Dyfyniad Arddull Chicago

National Geographic Society (U.S.). Special Publications Division. Preserving America's Past. Washington, D.C: The Society, 1983.

Dyfyniad MLA

National Geographic Society (U.S.). Special Publications Division. Preserving America's Past. The Society, 1983.

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