@misc{cryptoeprint:2002:137,
    author = {Nicholas J. Hopper and John Langford and Luis von Ahn},
    title = {Provably Secure Steganography},
    howpublished = {Cryptology ePrint Archive, Report 2002/137},
    year = {2002},
    url = {http://eprint.iacr.org/2002/137},
}