@Article{LangePolthierSimon,
  author =          "Carsten Lange AND Konrad Polthier AND Udo Simon",
  title =           "{Zur Geometrie von Fr{\"u}st{\"u}ckseiern}",
  journal =         "Math. Semesterberichte",
  year =            "2009",
  volume =          "56",
  pages =           "1-14"
}