Synchronic and Diachronic Approaches to Language: A Festschrift for Toshio Nakao on the Occasion of his sixtieth Birthday, S. Chiba, Y. Fujiwara, M. Ike-uchi, T. Kohno, O. Koma, Y, Nagahara, T. Namiki, Y. Otsu, M. Suiko, K. Ushie and N. Yamada (eds).