@book { MedienstdteinDeutschland,
    title = "Medienstädte in Deutschland",
    author = "Dirk {Drenk}",
    year = "2002",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783832449919",
    url = "https://m.diplom.de/document/220554"
}