@book { DieZeitstrukturderimplizitenVolatilitten,
    title = "Die Zeitstruktur der impliziten Volatilitäten",
    author = "Michael {Hoesgen}",
    year = "1998",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783832411732",
    url = "https://m.diplom.de/document/217096"
}