@misc{cryptoeprint:2014:537,
author = {Georg Fuchsbauer},
title = {Constrained Verifiable Random Functions},
howpublished = {Cryptology ePrint Archive, Report 2014/537},
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.