@book { EBusinessControllingimMarketingundVertriebsprozess,
    title = "E-Business-Controlling im Marketing und Vertriebsprozess",
    author = "Sven {Braun}",
    year = "2003",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783832464899",
    url = "https://m.diplom.de/document/221907"
}