@book { MessungderWerbeeffizienz,
    title = "Messung der Werbeeffizienz",
    subtitle = "Eine Untersuchung am Beispiel des ICE-Sprinters Berlin-Frankfurt am Main",
    author = "Katharina {Weh}",
    year = "2001",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783832430153",
    url = "https://m.diplom.de/document/218733"
}