@Book{soentgen2007selbstdenken,
  author = {jens Soentgen},
  title  = {Selbstdenken! 20 Praktiken der Philosophie},

  year   = {2007},
  number = {},
  url    = {http://www.worldcat.org/search?qt=worldcat_org_all&q=9783407755261},

  const  = {\ text}
}