APA-viite (7. p.)
National Geographic Society & National Geographic Society. (1975). THE INCREDIBLE INCAS AND THEIR TIMELESS LAND.
Chicago-viite (17. p.)
National Geographic Society ja National Geographic Society. THE INCREDIBLE INCAS AND THEIR TIMELESS LAND. 1975.
MLA-viite (9. p.)
National Geographic Society ja National Geographic Society. THE INCREDIBLE INCAS AND THEIR TIMELESS LAND. 1975.
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