@book { DasSchmerzBuch,
    title = "Das Schmerz-Buch",
    author = "Prof. Dr. med. Matthias {Karst}",
    year = "2015",
    publisher = "Schlütersche Verlagsgesellschaft mbH & Co. KG",
    address = ", Deutschland",
    url = "https://schluetersche.openpublishing.com/document/403937"
}