@misc{cryptoeprint:2012:406,
    author = {*Jue-Sam Chou 1, Yalin Chen2, Chun-Hui Huang 3, Yu-Siang Huang4},
    title = {Comments on four multi-server authentication protocols using smart card},
    howpublished = {Cryptology ePrint Archive, Report 2012/406},
    year = {2012},
    url = {http://eprint.iacr.org/2012/406},
}