@book { Lebensbilder,
    title = "Lebensbilder",
    subtitle = "Wie Fotos bei der Biografiearbeit helfen",
    author = "Ursula {Schmid}",
    year = "2013",
    publisher = "Schlütersche Verlagsgesellschaft mbH & Co. KG",
    address = ", Deutschland",
    url = "https://schluetersche.openpublishing.com/document/403805"
}