Henry S. Baird, Terry P. Riopka. ScatterType: a reading CAPTCHA resistant to segmentation attack. In Elisa H. Barney Smith, Kazem Taghva, editors, Document Recognition and Retrieval XII, 16-20 January 2005, San Jose, California, USA, Proceedings. Volume 5676 of SPIE Proceedings, pages 197-207, SPIE, 2005. [doi]
Abstract is missing.