Cryptology ePrint Archive: BibTeX Citation of Report 2010/275

@misc{cryptoeprint:2010:275,
    author = {Harry Buhrman, Nishanth Chandran and Serge Fehr and Ran Gelles and Vipul Goyal and Rafail Ostrovsky and Christian Schaffner},
    title = {Position-Based Quantum Cryptography: Impossibility and Constructions},
    howpublished = {Cryptology ePrint Archive, Report 2010/275},
    year = {2010},
    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.