@book { Personalentwicklung,
    title = "Personalentwicklung",
    author = "Karla {Kämmer}",
    year = "2014",
    publisher = "Schlütersche Verlagsgesellschaft mbH & Co. KG",
    address = ", Deutschland",
    url = "https://schluetersche.openpublishing.com/document/403854"
}