@inproceedings{ICPR-v3-2006-WangB06a,
	author        = "Sui-Yu Wang and Jon Louis Bentley",
	booktitle     = "{Proceedings of the 18th International Conference on Pattern Recognition, Volume 3}",
	doi           = "10.1109/ICPR.2006.355",
	isbn          = "0-7695-2521-0",
	pages         = "164--167",
	publisher     = "{IEEE Computer Society}",
	title         = "{CAPTCHA Challenge Tradeoffs: Familiarity of Strings versus Degradation of Images}",
	year          = 2006,
}