@article{TrautweinNagyMaaz2011,
  author    = {Ulrich Trautwein and Gabriel Nagy and Kai Maaz},
  title     = {Social disparities and the opening of the secondary school system in Germany},
  journal   = {Zeitschrift f{\"u}r Erziehungswissenschaft},
  volume    = {14},
  number    = {3},
  pages     = {445 -- 463},
  doi       = {10.1007/s11618-011-0220-5},
  year      = {2011},
}