Michael Rohs Johannes Schöning Martin Raubal Georg Essl Antonio Krüger Map navigation with mobile devices: virtual versus physical movement with and without visual context. 146-153 2007 ICMI http://doi.acm.org/10.1145/1322192.1322219 conf/icmi/2007 db/conf/icmi/icmi2007.html#RohsSREK07