Cryptology ePrint Archive: BibTeX Citation of Report 2015/891

@misc{cryptoeprint:2015:891,
    author = {S\'ebastien Canard and Viet Cuong Trinh},
    title = {Private Ciphertext-Policy Attribute-based Encryption Schemes With Constant-Size Ciphertext Supporting CNF Access Policy},
    howpublished = {Cryptology ePrint Archive, Report 2015/891},
    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.