National Geographic 1992-08, August
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Geocaching Magazin – November-Dezember 06, 2013
National Geographic Magazine 1979-12, December
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National Geographic Germany – Januar 01, 2014
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National Geographic 1995-05, May
National Geographic 1993-SE (Special Edition)
National Geographic 1994-08, August
National Geographic Magazine 1983-03, March
National Geographic Magazine 1981-11, November
National Geographic Magazine 1982-03, March
National Geographic Magazine 1984-12, December
National Geographic Magazine 1971-02, February
