@misc{cryptoeprint:2009:187,
author = {Rafael Misoczki and Paulo S. L. M. Barreto},
title = {Compact McEliece Keys from Goppa Codes},
howpublished = {Cryptology ePrint Archive, Report 2009/187},
year = {2009},
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.