Yoshifumi Saijo Takahiro Iwamoto Kazuto Kobayashi Satoshi Yamaguchi Hiroshi Tsunoda Hidehisa Nakayama Nei Kato Yoshiaki Nemoto Ultra-Mobile Echo Network in Health Care System. 164-166 2008 CBMS http://doi.ieeecomputersociety.org/10.1109/CBMS.2008.23 conf/cbms/2008 db/conf/cbms/cbms2008.html#SaijoIKYTNKN08