@book { Richtigessen,
    title = "Richtig essen",
    subtitle = "Der ganzheitliche Weg zu gesunder Ernährung",
    author = "Rüdiger  {Dahlke}",
    year = "2018",
    publisher = "dotbooks Verlag",
    address = "München, Germany",
    url = "https://www.dotbooks.de/document/427510"
}