APA-viite (7. p.)
National Geographic Society (U.S.). (1991). National Geographic picture atlas of our world. The National Geographic Society.
Chicago-viite (17. p.)
National Geographic Society (U.S.). National Geographic Picture Atlas of Our World. Washington D.C: The National Geographic Society, 1991.
MLA-viite (9. p.)
National Geographic Society (U.S.). National Geographic Picture Atlas of Our World. The National Geographic Society, 1991.
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