Cryptology ePrint Archive: BibTeX Citation of Report 2008/130

@misc{cryptoeprint:2008:130,
    author = {Florian Mendel and Norbert Pramstaller and Christian Rechberger and Vincent Rijmen},
    title = {Analysis of Step-Reduced SHA-256},
    howpublished = {Cryptology ePrint Archive, Report 2008/130},
    year = {2008},
    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.