@book { VerbesserungsweseninderAltenhilfe,
    title = "Verbesserungswesen in der Altenhilfe",
    author = "Stefan {Werner}",
    year = "2007",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783836604215",
    url = "https://m.diplom.de/document/228936"
}