@book { KaiserKonstantinundseinLeben,
    title = "Kaiser Konstantin und sein Leben",
    author = "Christiane {Eberle}",
    year = "2012",
    publisher = "GRIN Verlag",
    address = "München, Germany",
    doi = "10.3239/9783656228165",
    url = "https://www.hausarbeiten.de/document/196603"
}