@book { AssetAllocationmitImmobilien,
    title = "Asset Allocation mit Immobilien",
    author = "Holger {Wachter}",
    year = "2001",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783832448073",
    url = "https://m.diplom.de/document/220166"
}