@Inproceedings{grahl2007clustering,
  author = {Grahl, Miranda and Hotho, Andreas and Stumme, Gerd},
  title  = {Conceptual Clustering of Social Bookmarking Sites},

  year   = {2007},
  number = {},
  url    = {},

  const  = {\ text}
}
@Misc{santosneto-2007,
  author = {Santos-Neto, Elizeu and Ripeanu, Matei and Iamnitchi, Adriana},
  title  = {Tracking User Attention in Collaborative Tagging Communities},

  year   = {2007},
  number = {},
  url    = {http://arxiv.org/pdf/0705.1013},

  const  = {\ text}
}
@Article{begelman2006atc,
  author = {Begelman, G. and Keller, P. and Smadja, F.},
  title  = {Automated Tag Clustering: Improving search and exploration in the tag space},
  journal = {WWW2006, May},
  year   = {2006},
  number = {},
  url    = {http://www.pui.ch/phred/automated_tag_clustering/},

  const  = {\ text}
}
@Techreport{citeulike:739394,
  author = {Heymann, Paul and Garcia-Molina, Hector},
  title  = {Collaborative Creation of Communal Hierarchical Taxonomies in Social Tagging Systems},

  year   = {2006},
  number = {2006-10},
  url    = {http://dbpubs.stanford.edu:8090/pub/2006-10},

  const  = {\ text}
}
@Inproceedings{Mika2005,
  author = {Mika, Peter},
  title  = {Ontologies Are Us: A Unified Model of Social Networks and Semantics},

  year   = {2005},
  number = {},
  url    = {http://www.cs.vu.nl/~pmika/research/papers/ISWC-folksonomy.pdf},
  doi = {10.1007/11574620_38},
  const  = {\ text}
}