@book { AnanalysisofProductPlacementasastrategiccommunicationinstrument,
    title = "An analysis of Product Placement as a strategic communication instrument",
    author = "Michael {Knöppel}",
    year = "1999",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783832412661",
    url = "https://m.diplom.de/document/217180"
}