@misc{cryptoeprint:2013:412,
author = {Yuan Tian, Xueyong Zhu, Rongxin Sun},
title = {Moduar Form Aprroach to Solving Lattice Problems},
howpublished = {Cryptology ePrint Archive, Report 2013/412},
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.