@book { MesseEventsalsInstrumentderMessepolitik,
    title = "Messe-Events als Instrument der Messepolitik",
    author = "Sigrun {Grahm}",
    year = "2001",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783832435554",
    url = "https://m.diplom.de/document/219216"
}