@book { SecondLifeundMarketingindervirtuellenWelt,
    title = "Second Life und Marketing in der virtuellen Welt",
    author = "Simon {Borghardt}",
    year = "2008",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783836611640",
    url = "https://m.diplom.de/document/225703"
}