@book { DieBedeutungvonVirtualCommunitiesfrdasMarketing,
    title = "Die Bedeutung von Virtual Communities für das Marketing",
    subtitle = "Insbesondere für das Electronic Shopping",
    author = "Michael {Krauss}",
    year = "1999",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783832419660",
    url = "https://m.diplom.de/document/217810"
}