@InProceedings{McCPerRei2005,
  author =    {Jonathan M. Mc{C}une and Adrian Perrig and Michael K. Reiter},
  title =     {Seeing-Is-Believing: Using Camera Phones for Human-Verifiable Authentication},
  booktitle = {Proceedings of the IEEE Symposium on Security and Privacy},
  year =      2005,
  month =     may,
  url =       {http://www.ece.cmu.edu/~jmmccune/papers/mccunej_believing.pdf}
}