@electronic{www.mathe-spass.de,
   title       = {Knobeln Mathematischer Unfug}, 
   url         = {http://www.mathe-spass.de/error.htm},
   biburl      = {https://puma.uni-kassel.de/url/452693ebea7a7c040f014114c8be7551/stephandoerfel},
   keywords    = {beweis fehler knobeln mathe spass},
   added-at    = {2009-12-08T19:07:20.000+0100},
   description = {TrickBeweise, Paradoxa usw},
   interhash   = {452693ebea7a7c040f014114c8be7551}, 
   intrahash   = {452693ebea7a7c040f014114c8be7551}
}