@inproceedings{EfficientGroupAuthentication,
  title = "Efficient group authentication protocols based on human interaction",
  author = "A. W. Roscoe and L. H. Nguyen",
  year = "2006",
  booktitle = "{Proceedings of ARSPA 2006}",
  url = "http://web.comlab.ox.ac.uk/oucl/work/bill.roscoe/publications/116.pdf",
}