Dyfyniad APA

National Geographic Society (U.S.). Book Division. (1998). The wonders of the world. National Geographic Society.

Dyfyniad Arddull Chicago

National Geographic Society (U.S.). Book Division. The Wonders of the World. Washington, D.C: National Geographic Society, 1998.

Dyfyniad MLA

National Geographic Society (U.S.). Book Division. The Wonders of the World. National Geographic Society, 1998.

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