1. METI R3 Research Group (Ed.), “R3 – Real-time Remote Robotics,” Nikkan Kogyo Newspaper Co. Ltd., 1996 (in Japanese).
2. S. Maeyama, S. Yuta, and A. Harada, “Mobile robots in art museum for remote appreciation via internet,” In Proc. of 2002 International Conference on Intelligent Robots and Systems Workshop WS9 “Robots in Exhibitions,” pp. 23-28, 2002.
3. Y. Matsusaka, T. Tojo, S. Kubota, K. Furukawa, D. Tamiya, S. Fujie, and T. Kobayashi, “Multi-person conversation via multi-modal interface –a robot who communicate with multi-user–,” In Proc. of Euro speech 99, pp. 1723-1726, Budapest, Hungary, September 1999.
4. K. Nakadai, H. Nakajima, M. Murase, S. Kaijiri, K. Yamada, T. Nakamura, Y. Hasegawa, H. G. Okuno, and H. Tsujino, “Robust tracking of multiple sound sources by spatial integration of room and robot microphone arrays,” In Proc. of International Conference on Acoustics, Speech, and Signal Processing 2006, pp. 929-932, Toulouse, France, May 2006.
5. D. H. Johnson and D. E. Dugeon, “Array Signal Processing: Concepts and Techniques,” Prentice Hall PTR, 1993.