Cryptology ePrint Archive: BibTeX Citation of Report 2001/087

@misc{cryptoeprint:2001:087,
    author = {C. Blundo and S. Martìn and B. Masucci and C. Padrò},
    title = {A Linear Algebraic Approach to Metering Schemes},
    howpublished = {Cryptology ePrint Archive, Report 2001/087},
    year = {2001},
    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.