National geographic

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  Año 1968, Vol. 134, Número 2

  • South to Mexico City

    Wilbur E. Garrett

    págs. 145-192

    

  • The incredible salmon

    Clarence P. Idyll

    págs. 195-219

    

  • The age of sail lives on at mystic

    Alan Villiers

    págs. 220-238

    

  • Land of the ancient basques

    Robert Laxalt

    págs. 240-276

    

  • Crystals, magical servants of the space age

    Kenneth F. Weaver

    págs. 278-296