@book { BeschwerdemanagementinderVersicherungsbranche,
    title = "Beschwerdemanagement in der Versicherungsbranche",
    author = "Michael {Hain}",
    year = "2003",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783832462925",
    url = "https://m.diplom.de/document/221694"
}