Akinari Hoshi
Professor of Niigata University
Vice Chair, Department of Mathematics
Chair, Mathematical Science, Fundamental Sciences, Graduate School of Science and Technology
Department of Mathematics, Faculty of Science, Niigata University
8050 Ikarashi 2-no-cho, Nishi-ku, Niigata 950-2181, Japan
e-mail : hoshi +@+ math.sc.niigata-u.ac.jp (Please replace "+@+" to "@".)