National geographic

• 

  Año 1976, Vol. 150, Número 5

  • What's happening to our climate?

    Samuel W. Matthews

    págs. 576-615

    

  • Laboratory in a dirty sky

    Rudolf J. Engelmann, Vera Simons

    págs. 616-620

    

  • Riding the outlaw trail

    Robert Redford

    págs. 622-657

    

  • Life slowly changes in a remote Himalayan Kingdom

    John Scofield

    págs. 658-683

    

  • The pipeline: Alaska's troubled colossus

    Bryan Hodgson

    págs. 684-716