1. Institute for Innovative Research, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8550, Japan
2. Aix-Marseille Univ, Université de Toulon, CNRS, CPT, Marseille, France
3. Graduate School of Mathematical Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo 153-8914, Japan
4. Honorary Member of Academy of Romanian Scientists, Ilfov, nr. 3, Bucuresti, Romania
5. Accademia Peloritana dei Pericolanti, Palazzo Università, Piazza S. Pugliatti 1, 98122 Messina, Italy