@INPROCEEDINGS{coopis13-RTPZ,  
  AUTHOR    = {Paraskevi Raftopoulou and Christos Tryfonopoulos and Euripides G.M. Petrakis and Nikos Zevlis},  
  TITLE     = "{DS4: Introducing Semantic Friendship in Distributed Social Networks.}",  
  BOOKTITLE = "{Proceedings of the 21st International Conference on Cooperative Information Systems (CoopIS)}",  
  YEAR      = {2013},
  PAGES     = {185éÌŸ-203},  
  MONTH     = {September},  
  ADDRESS   = "{Graz, Austria}",
}