1. Tama Forest Science Garden, FFPRI, 1833-81 Todori, Hachioji, Tokyo 193-0843, Japan
2. Nature Study and Squirrel Research, 3 Bessyo, Minami-ku, Yokohama, Kanagawa 232-0064, Japan
3. Japan Forest Technology Association, 7 Rokuban-cho, Chiyoda-ku, Tokyo 102-0085, Japan