National Geographic Society (U.S.) Special Publications Division. (1979). Mysteries of the ancient world. The Society.
Citazione stile Chigago Style (17a edizione)National Geographic Society (U.S.) Special Publications Division. Mysteries of the Ancient World. Washington: The Society, 1979.
Citatione MLA (9a ed.)National Geographic Society (U.S.) Special Publications Division. Mysteries of the Ancient World. The Society, 1979.
Attenzione: Queste citazioni potrebbero non essere precise al 100%.