@book { CerysDasLiedderNachtigall,
    title = "Cerys: Das Lied der Nachtigall",
    author = "Theresa {Eisner}",
    year = "2024",
    publisher = "Selbstverlag",
    address = ", Deutschland",
    url = "https://tolino.openpublishing.com/document/1471152"
}