@misc{cryptoeprint:2014:546,
author = {Johannes Blömer and Jakob Juhnke and Christina Kolb},
title = {Anonymous and Publicly Linkable Reputation Systems},
howpublished = {Cryptology ePrint Archive, Report 2014/546},
year = {2014},
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.