@book { NatrlichZuckerfreiZuckerfreieErnhrungfrAnfnger,
    title = "Natürlich Zuckerfrei! – Zuckerfreie Ernährung für Anfänger",
    author = "Katharina {Janssen} and Sophia {Fröhlich}",
    year = "2021",
    publisher = "Kitchen Champions Verlag",
    address = ", Deutschland",
    url = "https://tolino.openpublishing.com/document/1059975"
}