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        en:
        
         - Description: A composite of images showing the diminishing  en:Lake Chad from 1973 to 2001.
 
         - Info: The large image is a composite of photos taken with  en:Landsat-7. Images courtesy NASA GSFC Scientific Visualization Studio and Landsat 7 Project Science Office.
 
         - Source:  earth observatory  (file)
 
         - License: Public domain  
 
        
        de:
        
         - Beschreibung: Der  de:Tschadsee schrumpft langfristig. Das Bild zeigt den See im Jahr 1973, 1978, 1997 und 2001 aus der Erdumlaufbahn. Die offene Wasserfläche ist im Falschfarbeninfrarotbild blaugrün wiedergegeben.
 
         - Quelle: Adapted from NASA images at  http://earthobservatory.nasa.gov/Newsroom/NewImages/images.php3?img_id=4714 (aus der englischen Wikipedia)
 
         - Lizenzstatus: Public Domain
 
        
         Licensing 
        
         
          
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           This file is in the  public domain because it was solely created by  NASA. NASA copyright policy states that "NASA material is not protected by copyright unless noted". (See  Template:PD-USGov,  NASA copyright policy page or  JPL Image Use Policy.) | 
           
            
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       File usage
       
        The following pages on Schools Wikipedia link to this image (list may be incomplete):