Shinya Oyama Ikuko Eguchi Yairi Seiji Igi Takuichi Nishimura Walking Support Using Compact Terminals with Infrared Audio Communication. 468-475 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=3118&spage=468 2004 conf/icchp/2004 ICCHP db/conf/icchp/icchp2004.html#OyamaYIN04