1. INAF – Osservatorio Astronomico di Capodimonte,Napoli,Italy,80131
2. Instituto Nacional de Técnica Aeroespacial (INTA),Madrid,Spain
3. INAF – Astrophysics and Space Science Observatory (OAS),Bologna,40129
4. INAF – Institute for Space Astrophysics and Planetology (IAPS),Rome,Italy,00133
5. IKI – Space Research Institute,Moscow,Russia