@misc{cryptoeprint:2012:411,
author = {Alexander Dibert and Laszlo Csirmaz},
title = {Infinite Secret Sharing -- Examples},
howpublished = {Cryptology ePrint Archive, Report 2012/411},
year = {2012},
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.