@book { ZurBedeutungdesRisikomanagementsimMittelstand,
    title = "Zur Bedeutung des Risikomanagements im Mittelstand",
    author = "Petra {Lehmeyer}",
    year = "2012",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783842839335",
    url = "https://m.diplom.de/document/229298"
}