@misc{cryptoeprint:2013:465,
author = {Ioana Boureanu and Aikaterini Mitrokotsa and Serge Vaudenay},
title = {Practical & Provably Secure Distance-Bounding},
howpublished = {Cryptology ePrint Archive, Report 2013/465},
year = {2013},
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.