@inproceedings{au2009user,
  title = "User-induced links in collaborative tagging systems",
  author = "Au Yeung and Ching-man and Gibbins, Nicholas and Shadbolt, Nigel",
  year = "2009",
  booktitle = "Proceedings of the 18th ACM conference on Information and knowledge management",
  organization = "ACM",
  pages = "787--796",
}