R. Jesus, D. Goncalves, A. Abrantes, и N. Correia. Computer Vision and Pattern Recognition Workshops, 2008. CVPR Workshops 2008. IEEE Computer Society Conference on(Июнь 2008)
L. von Ahn, и L. Dabbish. CHI '04: Proceedings of the SIGCHI conference on Human factors in computing systems, стр. 319--326. New York, NY, USA, ACM, (2004)
B. Zhu, J. Yan, Q. Li, C. Yang, J. Liu, N. Xu, M. Yi, и K. Cai. CCS '10: Proceedings of the 17th ACM conference on Computer and communications security, стр. 187--200. New York, NY, USA, ACM, (Октябрь 2010)
R. Yan, A. Natsev, и M. Campbell. MS '07: Workshop on multimedia information retrieval on The many faces of multimedia semantics, стр. 13--20. New York, NY, USA, ACM, (2007)