[1] Waseda Univ, Dept Appl Phys, Okubo 3-4-1,Shinjuku Ku, Tokyo 1698555, Japan
[2] Univ Milano Bicocca, Dipartimento Matemat & Applicaz, Via Cozzi 55, I-20125 Milan, Italy
[3] Nazarbayev Univ, Dept Math, Kabanbay Batyr Ave 53, Astana 010000, Kazakhstan