@book { DieStieffamilie,
    title = "Die Stieffamilie",
    author = "Gernot {Mayer}",
    year = "1999",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783832414757",
    url = "https://m.diplom.de/document/217324"
}