(1995). Above the Rockies: Through digital eyes ; Heart of the Rockies 1:2 847 000 = Heart of the Rockies. National Geographic Society.
Chicago-viite (17. p.)Above the Rockies: Through Digital Eyes ; Heart of the Rockies 1:2 847 000 = Heart of the Rockies. Washington: National Geographic Society, 1995.
MLA-viite (9. p.)Above the Rockies: Through Digital Eyes ; Heart of the Rockies 1:2 847 000 = Heart of the Rockies. National Geographic Society, 1995.
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