@book { DergroehumboldtFotolehrgang,
    title = "Der große humboldt Fotolehrgang",
    author = "Tom! {Striewisch}",
    year = "2012",
    publisher = "humboldt",
    address = "Hannover, Deutschland",
    url = "https://schluetersche.openpublishing.com/document/403218"
}