@book { ImmobilienzykleninDeutschland,
    title = "Immobilienzyklen in Deutschland",
    subtitle = "Ursachen und empirische Analyse",
    author = "Nico {Rottke}",
    year = "2002",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783832452278",
    url = "https://m.diplom.de/document/220752"
}