@phdthesis{schefels.AnalyzingUserFeedbackOfOn-LineCommunities,
  author    = {Schefels, Clemens},
  title     = {Analyzing User Feedback of On-Line Communities},
  isbn      = {9783843912273},
  school    = {Goethe-University Frankfurt am Main},
  year      = {2013}
  publisher = {Dr. Hut},
  address   = {Munich, Germany}
}