@book { ParteienimNetz,
    title = "Parteien im Netz",
    subtitle = "Politische Werbung im Internet",
    author = "Lorenz {Steinke}",
    year = "1999",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    url = "https://m.diplom.de/document/217730"
}