Cryptology ePrint Archive: BibTeX Citation of Report 2009/178

@misc{cryptoeprint:2009:178,
    author = {Jiali Choy and Guanhan Chew and Khoongming Khoo and Huihui Yap},
    title = {Cryptographic Properties and Application of a Generalized Unbalanced Feistel Network Structure (Revised Version)},
    howpublished = {Cryptology ePrint Archive, Report 2009/178},
    year = {2009},
    note = {\url{http://eprint.iacr.org/}},
}

You will need the url.sty package (comes with most LaTeX installations) for the last line. Otherwise, remove the \url command.