Takahiro Kawamura Keisuke Umezu Akihiko Ohsuga Mobile Navigation System for the Elderly - Preliminary Experiment and Evaluation. 578-590 2008 UIC http://dx.doi.org/10.1007/978-3-540-69293-5_45 conf/uic/2008 db/conf/uic/uic2008.html#KawamuraUO08