@Book{staheli2000poststrukturalistische,
  author = {Stäheli, Urs},
  title  = {Poststrukturalistische Soziologien},

  year   = {2000},
  number = {},
  url    = {http://scans.hebis.de/HEBCGI/show.pl?09111502_toc.pdf},

  const  = {\ text}
}
@Book{sen2010gerechtigkeit,
  author = {Sen, Amartya},
  title  = {Die Idee der Gerechtigkeit},

  year   = {2010},
  number = {},
  url    = {http://d-nb.info/1000878090/04},

  const  = {\ text}
}
@Book{sen1999development,
  author = {Sen, Amartya},
  title  = {Development as freedom},

  year   = {1999},
  number = {},
  url    = {},

  const  = {\ text}
}