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  title  = {Recommender Systems for Social Tagging Systems},

  year   = {2012},
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  url    = {http://link.springer.com/book/10.1007/978-1-4614-1894-8},
  doi = {10.1007/978-1-4614-1894-8},
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@Book{balbymarinho2012recommender,
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  title  = {Recommender Systems for Social Tagging Systems},

  year   = {2012},
  number = {},
  url    = {http://link.springer.com/book/10.1007/978-1-4614-1894-8},
  doi = {10.1007/978-1-4614-1894-8},
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@Book{balbymarinho2012recommender,
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  title  = {Recommender Systems for Social Tagging Systems},

  year   = {2012},
  number = {},
  url    = {http://www.springer.com/computer/database+management+%26+information+retrieval/book/978-1-4614-1893-1},

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@Book{balbymarinho2012recommender,
  author = {Balby Marinho, L. and Hotho, A. and Jäschke, R. and Nanopoulos, A. and Rendle, S. and Schmidt-Thieme, L. and Stumme, G. and Symeonidis, P.},
  title  = {Recommender Systems for Social Tagging Systems},

  year   = {2012},
  number = {},
  url    = {http://link.springer.com/book/10.1007/978-1-4614-1894-8},
  doi = {10.1007/978-1-4614-1894-8},
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