Akio Shiibashi Tsuyoshi Nakaniwa Motoharu Yamana Kinji Mori Multi-layered Data Consistency Technology, An Enhanced Autonomous Decentralized Data Consistency Technology for IC Card Ticket System. 219-226 2007 conf/hase/2007 HASE http://doi.ieeecomputersociety.org/10.1109/HASE.2007.55 db/conf/hase/hase2007.html#ShiibashiNYM07