Seon-Yeong Kim, Sora Kim, Hwan-Gue Cho. A New Human Interactive Proof System Using Arbitrary and Fractal Polygon Image. In 11th IEEE International Conference on Computer and Information Technology, CIT 2011, Pafos, Cyprus, 31 August-2 September 2011. pages 261-268, IEEE Computer Society, 2011. [doi]
Abstract is missing.