@article{oai:shizuoka.repo.nii.ac.jp:00014019,
 author = {Nishigaki, Masakatsu and Koike, Makoto},
 issue = {2},
 journal = {Journal of Systemics, Cybernetics and Informatics},
 month = {},
 note = {application/pdf},
 pages = {18--23},
 title = {A User Authentication Based on Personal History : A User Authentication System Using E-mail History},
 volume = {5},
 year = {2007}
}