Cryptology ePrint Archive: BibTeX Citation of Report 2012/425

@misc{cryptoeprint:2012:425,
    author = {Gautham Sekar},
    title = {The Stream Cipher Core of the 3GPP Encryption Standard 128-EEA3: Timing Attacks and Countermeasures},
    howpublished = {Cryptology ePrint Archive, Report 2012/425},
    year = {2012},
    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.