National Geographic Society. Special Publications Division. (1986). Builders of the ancient world: Marvels of engineering. The Society.
Citazione stile Chigago Style (17a edizione)National Geographic Society. Special Publications Division. Builders of the Ancient World: Marvels of Engineering. Washington, D.C: The Society, 1986.
Citatione MLA (9a ed.)National Geographic Society. Special Publications Division. Builders of the Ancient World: Marvels of Engineering. The Society, 1986.
Attenzione: Queste citazioni potrebbero non essere precise al 100%.