@book { DerAntiKrebsRatgeber,
    title = "Der Anti-Krebs-Ratgeber",
    author = "Dr. Andrea {Flemmer}",
    year = "2019",
    publisher = "humboldt",
    address = "Hannover, Deutschland",
    url = "https://schluetersche.openpublishing.com/document/500325"
}