Thomas Kahlisch, Matthias Leopold and Christian Waldvogel (November 2004). «Computers Helping People with Special Needs: 9th International Conference, ICCHP 2004, Paris, France, July 7-9, 2004 : Proceedings». Computers Helping People with Special Needs. Lecture Notes in Computer Science; vol. 3118. 3118. Berlin / Heidelberg: Springer, σσ. 224–227. doi:10.1007/978-3-540-27817-7_34. ISBN978-3-540-22334-4.