Thorsten Völkel Romina Kühn Gerhard Weber Mobility Impaired Pedestrians Are Not Cars: Requirements for the Annotation of Geographical Data. 1085-1092 2008 ICCHP http://dx.doi.org/10.1007/978-3-540-70540-6_163 conf/icchp/2008 db/conf/icchp/icchp2008.html#VolkelKW08