P. Ehlen, M. Johnston, and G. Vasireddy. Proceedings of ICSLP---Interspeech 2002: 7th International Conference on Spoken Language Processing, Denver, CO, USA, page 2557-2560. (2002)
R. Schneider, and P. Heisterkamp. Proceedings of the ISCA Tutorial and Research Workshop (ITRW) on Interactive Dialogue in Multi-Modal Systems (IDS-02): Multi-Modal Dialogue in Mobile Environments. Kloster Irsee, Germany, (2002)
S. Watanabe, J. Hershey, Y. Marks, Tim K. Fujii, and Y. Koji. Proceedings of INTERSPEECH 2014, 15th Annual Conference of the International Speech Communication Association, Singapore, page 323-327. (2014)