Cryptology ePrint Archive: BibTeX Citation of Report 2007/250

@misc{cryptoeprint:2007:250,
    author = {Hongzhen Du and Qiaoyan Wen},
    title = {Efficient and Provably-Secure Certificateless Short Signature Scheme from Bilinear Pairings},
    howpublished = {Cryptology ePrint Archive, Report 2007/250},
    year = {2007},
    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.