@book { DieKontroversenberdenExtremismusderMitte,
    title = "Die Kontroversen über den Extremismus der Mitte",
    author = "Richard {Gebhardt}",
    year = "2005",
    publisher = "GRIN Verlag",
    address = "München, Germany",
    doi = "10.3239/9783640073764",
    url = "https://www.hausarbeiten.de/document/109194"
}