@inproceedings{shirali2007question,
  author    = {M. Shirali-Shahreza and S. Shirali-Shahreza},
  title     = {Question-Based CAPTCHA},
  booktitle = {Proceedings of the International Conference on Computational Intelligence and Multimedia Applications (ICCIMA 2007)},
  address   = {Sivakasi, India},
  month     = dec,
  year      = {2007},
  volume    = {4},
  pages     = {54--58},
  doi       = {10.1109/ICCIMA.2007.363},
  url       = {https://doi.org/10.1109/ICCIMA.2007.363}
}