@article{Engel1997,
  author    = {Engel, Dirk},
  title     = {Der Minderheitenschutz in Vergangenheit und Gegenwart},
  isbn      = {3-87061-606-7},
  year      = {1997},
  language  = {de}
}
@article{Engel1997,
  author    = {Engel, Dirk},
  title     = {Die sprachenrechtliche Situation von Minderheiten},
  isbn      = {3-87061-606-7},
  year      = {1997},
  language  = {de}
}