@misc{cryptoeprint:2011:696,
author = {Dario Catalano and Dario Fiore and Bogdan Warinschi},
title = {Efficient Network Coding Signatures in the Standard Model},
howpublished = {Cryptology ePrint Archive, Report 2011/696},
year = {2011},
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.