Institution: | 1. Université de Pau, Laboratoire de Mathématiques et de leurs Applications, CNRS UMR 5142, av. de l’Université, 64000 Pau, France;2. Institute for Low Temperature Physics & Engineering, 47, av. Lenin, 61103, Kharkov, Ukraine;3. Narvik University College, Postbox 385, Narvik, 8505, Norway;4. Lebedev Physical Institute RAS, Leninski prospect 53, Moscow, 119991, Russia |