@book { BioLebensmittel,
    title = "Bio-Lebensmittel",
    subtitle = "Nachhaltig einkaufen, gesund leben. Mit einem Vorwort von Sarah Wiener",
    author = "Dr. Andrea {Flemmer}",
    year = "2021",
    publisher = "humboldt",
    address = "Hannover, Deutschland",
    url = "https://schluetersche.openpublishing.com/document/1108900"
}