Hartwig, G. (1881). The polar world: A popular description of man and nature in the Arctic and Antarctic regions of the globe (Segunda edición.). Longmans, Green, and Co.
Čikaški stil citiranja (17. izdanje)Hartwig, G. The Polar World: A Popular Description of Man and Nature in the Arctic and Antarctic Regions of the Globe. Segunda edición. London, England, United Kingdom: Longmans, Green, and Co, 1881.
MLA način citiranja (9. izdanje)Hartwig, G. The Polar World: A Popular Description of Man and Nature in the Arctic and Antarctic Regions of the Globe. Segunda edición. Longmans, Green, and Co, 1881.
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