1. Department of Theoretical Physics Horia Hulubei National Institute of Physics and Nuclear Engineering Măgurele Romania
2. Faculty of Physics University of Bucharest Bucharest–Măgurele Romania
3. Leibniz Centre for Tropical Marine Research Bremen Germany
4. Niels Bohr Institute Copenhagen University Copenhagen Denmark
5. Physics and Earth Sciences Constructor University Bremen Germany
6. Institute of Physics and Astronomy University of Potsdam Potsdam Germany