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National Geographic : reprinted from the May, 1961 magazine | Hefte | 910.92 Wea
Weaver, Kenneth F. / - Washington, D.C. : National Geographic Society, 1961. [Hefte]. - s. 702-734 - Språk: Engelsk | Weaver, Kenneth F. | 1961 |
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National Geographic : reprinted from the September, 1961 magazine | Hefte | 910.92 Jac
Jackson, Carmault B. / - Washington, D.C. : National Geographic Society, 1961. [Hefte]. - s. 416-444 - Språk: Engelsk | Jackson, Carmault B. | 1961 |
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National Geographic : reprinted from the July, 1960 magazine | Hefte | 910.92 Fis
Fisher, Jr., Allan C. / - Washington, D.C. : National Geographic Society, 1960. [Hefte]. - s. 48-89 - Språk: Engelsk | Fisher, Jr., Allan C. | 1960 |