@unpublished{Lankau2013,
  author  = {Ralf Lankau},
  title   = {Mathematik aus G{\"u}tersloh},
  institution = {Fakult{\"a}t Medien und Informationswesen (M+I) (bis 21.04.2021)},
  year    = {2013},
  language  = {de}
}