With M. Ruoß & W. Schaller, Sprachvisualisierung unter Berücksichtigung psychoakustischer Wahrnehmungseigenschaften, in Fortschritte der Akustik - DAGA ’87, Verlag DPG-GmbH, Bad Honnef, 1987, pp. 673-676.

With M. Ruoß & M. Drautzburg, Visible Speech - Examination of Different Patterns and Development of a New Speech Visualizer, in Proceedings of the 7th Symposium of the Federation of Acoustical Societies of Europe (FASE), Institute of Acoustics, Edinburgh, 1988, pp. 187-194.