@book { InformationsundKommunikationssystemeinderTagungsundKongressbranche,
    title = "Informations- und Kommunikationssysteme in der Tagungs- und Kongressbranche",
    author = "Bianca {Hirsch}",
    year = "2001",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783832444495",
    url = "https://m.diplom.de/document/220056"
}