Fraser Newton, Michael A. Kouritzin. On grey levels in random CAPTCHA generation. In Zia-ur Rahman, Stephen E. Reichenbach, Mark A. Neifeld, editors, Visual Information Processing XX, 25 April 2010, Orlando, Florida, USA. Volume 8056 of SPIE Proceedings, SPIE, 2011. [doi]
@inproceedings{NewtonK11, title = {On grey levels in random CAPTCHA generation}, author = {Fraser Newton and Michael A. Kouritzin}, year = {2011}, doi = {10.1117/12.884124}, url = {http://dx.doi.org/10.1117/12.884124}, researchr = {https://researchr.org/publication/NewtonK11}, cites = {0}, citedby = {0}, booktitle = {Visual Information Processing XX, 25 April 2010, Orlando, Florida, USA}, editor = {Zia-ur Rahman and Stephen E. Reichenbach and Mark A. Neifeld}, volume = {8056}, series = {SPIE Proceedings}, publisher = {SPIE}, isbn = {978-0-8194-8630-1}, }