@book { PassauunddasNibelungenlied,
    title = "Passau und das Nibelungenlied",
    author = "Ulrike {Ziegler}",
    year = "2006",
    publisher = "GRIN Verlag",
    address = "München, Germany",
    doi = "10.3239/9783638498814",
    url = "https://www.hausarbeiten.de/document/54759"
}