@book { SerbischEinfacheStze1,
    title = "Serbisch: Einfache Sätze 1",
    author = "Snezana {Stefanovic}",
    year = "2020",
    publisher = "via tolino media",
    address = "München, Deutschland",
    url = "https://tolino.openpublishing.com/document/1378288"
}