@article{WestphalGronostajVocketal.2016,
  author    = {Andrea Westphal and Anna Gronostaj and Miriam Vock and Rico Emmrich and Peter Harych},
  title     = {Differentiation in Mathematics and in German Lessons on Grammar School Level Is it to be found mainly among good diagnosticians and in heterogeneous classes?},
  journal   = {Zeitschrift f{\~A}¼r P{\~A}\idagogik},
  volume    = {62},
  pages     = {131 -- 148},
  year      = {2016},
}