@misc{cryptoeprint:2002:151,
author = {Jason E. Holt and Kent E. Seamons},
title = {Selective disclosure credential sets},
howpublished = {Cryptology ePrint Archive, Report 2002/151},
year = {2002},
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.