@book { GrundlagenundinstrumentelleAusgestaltungdesoperativenMarketingcontrollings,
    title = "Grundlagen und instrumentelle Ausgestaltung des operativen Marketingcontrollings",
    author = "Tom {Sieber}",
    year = "2005",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783832486631",
    url = "https://m.diplom.de/document/223857"
}