@misc{cryptoeprint:2012:689,
    author = {Abishek Kumarasubramanian and Rafail Ostrovsky and Omkant Pandey and Akshay Wadia},
    title = {Cryptography Using CAPTCHA Puzzles},
    howpublished = {Cryptology ePrint Archive, Report 2012/689},
    year = {2012},
    url = {http://eprint.iacr.org/2012/689},
}