@article{statisticalanalysisofdicecaptcha,
  title = {Statistical Analysis of Dice CAPTCHA Usability},
  author = {Darko Brodić and Alessia Amelio and Ivo R. Draganov},
  year = {2017},
  eprint = {1706.10177},
  archivePrefix = {arXiv},
  url = {http://arxiv.org/abs/1706.10177v1},
}