@book { GatedCommunitiesalsneueWohnforminSdfrankreich,
    title = "Gated Communities als neue Wohnform in Südfrankreich",
    author = "Stephan {Bernhard}",
    year = "2002",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    url = "https://m.diplom.de/document/220960"
}