@misc{cryptoeprint:2010:447,
author = {Olivier Benoit and Thomas Peyrin},
title = {Side-channel Analysis of Six SHA-3 Candidates},
howpublished = {Cryptology ePrint Archive, Report 2010/447},
year = {2010},
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.