@book { Qualittssicherung,
    title = "Qualitätssicherung",
    author = "Christiane {Panka} and Karla {Kämmer}",
    year = "2015",
    publisher = "Schlütersche Verlagsgesellschaft mbH & Co. KG",
    address = ", Deutschland",
    url = "https://schluetersche.openpublishing.com/document/403904"
}