Hiroshi Dozono Daichi Takata Masanori Nakakuni Yoshio Noguchi The Analysis of Pen Pressures of Handwritten Symbols on PDA Touch Panel using Self Orgazining Maps. 440-445 2005 conf/csreaSAM/2005 Security and Management db/conf/csreaSAM/csreaSAM2005.html#DozonoTNN05