@unpublished{GeisselKraemlingPaulus2019,
  author  = {Brigitte Geißel and Anna Kr{\"a}mling and Lars Paulus},
  title   = {More or less equality? Direct Democracy in Europe from 1990 to 2015},
  institution = {Gesellschaftswissenschaften},
  pages     = {37},
  year    = {2019},
}