@misc{cryptoeprint:2015:764,
author = {Jincheng Zhuang and Qi Cheng},
title = {On Generating Coset Representatives of PGL_2(\F_q) in PGL_2(\F_{q^2})},
howpublished = {Cryptology ePrint Archive, Report 2015/764},
year = {2015},
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.