Παραπομπή σε μορφή APA (7η εκδ.)

National Geographic Socity. Special Publication Division & Gray, W. B. (1978). Power of nature. Prepared by the Special Publication Division, National Geographic Society.

Παραπομπή σε μορφή Chicago (17η εκδ.)

National Geographic Socity. Special Publication Division και William B. Gray. Power of Nature. Washington, DC: Prepared by the Special Publication Division, National Geographic Society, 1978.

Παραπομπή σε μορφή MLA (9th εκδ.)

National Geographic Socity. Special Publication Division και William B. Gray. Power of Nature. Prepared by the Special Publication Division, National Geographic Society, 1978.