@misc{cryptoeprint:2013:481,
author = {Yosuke Todo and Keita Xagawa},
title = {Cryptanalysis of the Huang-Liu-Yang Cryptosystem from PKC 2012},
howpublished = {Cryptology ePrint Archive, Report 2013/481},
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.