Cryptology ePrint Archive: BibTeX Citation of Report 2005/022

@misc{cryptoeprint:2005:022,
    author = {ChangKyun Kim and JaeCheol Ha and SangJae Moon and Sung-Ming Yen and Wei-Chih Lien and  Sung-Hyun Kim},
    title = {An Improved and Efficient Countermeasure against Power Analysis Attacks},
    howpublished = {Cryptology ePrint Archive, Report 2005/022},
    year = {2005},
    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.