@inproceedings{HCI-UA-2011-HsuL,
	author        = "Chih-Hsiang Hsu and Ying-Lien Lee",
	booktitle     = "{Proceedings of the 14th International Conference on Human-Computer Interaction. Part IV: Users and Applications}",
	doi           = "10.1007/978-3-642-21619-0_56",
	isbn          = "978-3-642-21618-3",
	pages         = "453--455",
	publisher     = "{Springer International Publishing}",
	series        = "{Lecture Notes in Computer Science}",
	title         = "{Effects of Age Groups and Distortion Types on Text-Based CAPTCHA Tasks}",
	volume        = 6764,
	year          = 2011,
}