National geographic

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  Año 1937, Vol. 71, Número 6

  • Washington, home city and show place

    Leo A. Borah

    págs. 663-696

    

  • Hunting with a microphone the voices of vanishing birds

    Arthur A. Allen

    págs. 697-724

    

  • In the empire of the Aztecs

    Frank H. H. Roberts

    págs. 725-750

    

  • Men against the rivers

    Frederick Simpich

    págs. 767-794

    

  • A modern pilgrim's map of the British isles

    Andrew H. Brown

    págs. 795-802