@book { KreditratingnachBaselII,
    title = "Kreditrating nach Basel II",
    author = "Stefan {Schmidt}",
    year = "2003",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783832471880",
    url = "https://m.diplom.de/document/222493"
}