National Geographic society. (1992). Beyond the horizon: Adventures in faraway lands. National Geographic Society.
Chicago-viite (17. p.)National Geographic society. Beyond the Horizon: Adventures in Faraway Lands. Washington, D.C.: National Geographic Society, 1992.
MLA-viite (9. p.)National Geographic society. Beyond the Horizon: Adventures in Faraway Lands. National Geographic Society, 1992.
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