@misc{cryptoeprint:2015:369,
author = {Nir Bitansky and Omer Paneth},
title = {On Non-Black-Box Simulation and the Impossibility of Approximate Obfuscation},
howpublished = {Cryptology ePrint Archive, Report 2015/369},
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.