@book { DieMigrationspolitikderEU,
    title = "Die Migrationspolitik der EU",
    subtitle = "Notwendigkeit, Anspruch und Realität",
    author = "Marco {Kaden}",
    year = "2009",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    url = "https://m.diplom.de/document/226779"
}