Designing human friendly human interaction proofs (HIPs)

Kumar Chellapilla, Kevin Larson, Patrice Y. Simard, Mary Czerwinski. Designing human friendly human interaction proofs (HIPs). In Gerrit C. van der Veer, Carolyn Gale, editors, Proceedings of the 2005 Conference on Human Factors in Computing Systems, CHI 2005, Portland, Oregon, USA, April 2-7, 2005. pages 711-720, ACM, 2005. [doi]

Abstract

Abstract is missing.