1. Yasuyuki Sumi, Tameyuki Etani, and Kenji Mase. Context-aware mobile assistant. In 55th Annual Convention of Information Processing Society of Japan, volume 4, pages 443–444. September 1997. in Japanese.
2. Kenji Mase, Yasuyuki Sumi, Tameyuki Etani, Kaoru Kobayashi, Sidney Fels, Nicolas Simonet, and Rieko Kadobayashi. Personal and mobile interface agents for exhibition guiding. In Third Symposium on Intelligent Information Media, pages 219–224. IEICE, December 1997. in Japanese.
3. Sidney Fels, Yasuyuki Sumi, Tameyuki Etani, Nicolas Simonet, Kaoru Kobayashi, and Kenji Mase. Progress of C-MAP: A context-aware mobile assistant. In AAAI Spring Symposium on Intelligent Environments, pages 60–67. March 1998.
4. Mark Stefik. The next knowledge medium. AI Magazine, 7(1):34–46, 1986.
5. Rieko Kadobayashi and Kenji Mase. MetaMuseum as a new communication environment. In Multimedia Communication and Distributed Processing System Workshop, pages 71–78. Information Processing Society of Japan, 1995. in Japanese.