@book { MarkenaufvirtuellenMrkten,
    title = "Marken auf virtuellen Märkten",
    author = "Karina {Preiß}",
    year = "2001",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783832448233",
    url = "https://m.diplom.de/document/220399"
}