@misc{cryptoeprint:2014:655,
author = {Bo Zhu and Xinxin Fan and Guang Gong},
title = {Pleco and Plectron -- Two Provably Secure Password Hashing Algorithms},
howpublished = {Cryptology ePrint Archive, Report 2014/655},
year = {2014},
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.