@book { RisikomanagementbeiImmobilienfinanzierungen,
    title = "Risikomanagement bei Immobilienfinanzierungen",
    author = "Oliver {Boldt}",
    year = "2001",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783832446697",
    url = "https://m.diplom.de/document/220278"
}