Henry S. Baird, Jon Louis Bentley. Implicit CAPTCHAs. In Elisa H. Barney Smith, Kazem Taghva, editors, Document Recognition and Retrieval XII, 16-20 January 2005, San Jose, California, USA, Proceedings. Volume 5676 of SPIE Proceedings, pages 191-196, SPIE, 2005. [doi]
@inproceedings{BairdB05,
title = {Implicit CAPTCHAs},
author = {Henry S. Baird and Jon Louis Bentley},
year = {2005},
url = {http://www.imaging.org/store/epub.cfm?abstrid=32864},
researchr = {https://researchr.org/publication/BairdB05},
cites = {0},
citedby = {0},
pages = {191-196},
booktitle = {Document Recognition and Retrieval XII, 16-20 January 2005, San Jose, California, USA, Proceedings},
editor = {Elisa H. Barney Smith and Kazem Taghva},
volume = {5676},
series = {SPIE Proceedings},
publisher = {SPIE},
isbn = {0-8194-5649-7},
}