National Geographic Society (U.S.), McGraw-Hill Companies. McGraw-Hill School Division, & Banks, J. A. (2000). Regions: Adventure in time and place. McGraw-Hill.
Chicago-viite (17. p.)National Geographic Society (U.S.), McGraw-Hill Companies. McGraw-Hill School Division, ja James A. Banks. Regions: Adventure in Time and Place. New York, N.Y.: McGraw-Hill, 2000.
MLA-viite (8. p.)National Geographic Society (U.S.), et al. Regions: Adventure in Time and Place. McGraw-Hill, 2000.
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