@article{oai:ipsj.ixsq.nii.ac.jp:00063338, author = {前川, 徹 and Maegawa, Toru}, issue = {12}, journal = {情報処理}, month = {Dec}, title = {情報セキュリティ歳時記:不正アクセスの実態と対策(その4)}, volume = {40}, year = {1999} }