User Feed-Back in the Development of an Information System for Public Transport. - Christian Bühler; Helmut Heck; Christian Radek; Rainer Wallbruch; Josef Becker; Claudia Bohner-Degrell (ICCHP (1), 2010)

Meldestelle für digitale Barrieren. - Christian Bühler; Christian Radek (GI-Jahrestagung, 2015)