%0 Journal Article %1 ahn04 %A von Ahn, Luis %A Blum, Manuel %A Langford, John %D 2004 %J Communications of the ACM %K imported %N 2 %P 56-60 %R 10.1145/966389.966390 %T Telling Humans and Computers Apart Automatically %V 47

@article{ahn04, added-at = {2009-01-14T00:43:43.000+0100}, author = {von Ahn, Luis and Blum, Manuel and Langford, John}, biburl = {https://www.bibsonomy.org/bibtex/23c164d7cd6a63bba0c4671f16356137c/dret}, description = {dret'd bibliography}, doi = {10.1145/966389.966390}, interhash = {7f11e91eeb91e37737743bcd908b38fd}, intrahash = {3c164d7cd6a63bba0c4671f16356137c}, journal = {Communications of the ACM}, keywords = {imported}, month = {February}, number = 2, pages = {56-60}, timestamp = {2009-01-14T00:43:45.000+0100}, title = {Telling Humans and Computers Apart Automatically}, topic = {captcha[1]}, uri = {http://www.cs.cmu.edu/~biglou/captcha_cacm.pdf}, volume = 47, year = 2004 }