@book { HowimportantisWeb20forthetourismsectorandhowcantheindustryapplytothistrend,
    title = "How important is Web 2.0 for the tourism sector and how can the industry apply to this trend?",
    author = "Tim {Lellinger}",
    year = "2010",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783842806894",
    url = "https://m.diplom.de/document/228150"
}