@book { DasHandyVertriebswegderZukunft,
    title = "Das Handy - Vertriebsweg der Zukunft?",
    author = "Gundula {Gross}",
    year = "2001",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783832441395",
    url = "https://m.diplom.de/document/219763"
}