1. Nordita, KTH Royal Institute of Technology and Stockholm University, Roslagstullsbacken 23, SE-10691 Stockholm, Sweden
2. Tuorla Observatory, University of Turku, Väisäläntie 20, FI-21500 Piikkiö, Finland
3. Department of Physics and Astronomy, University of Southampton, Highfield, Southampton SO17 1BJ, UK
4. Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA 70803-4001, USA
5. Finnish Centre for Astronomy with ESO (FINCA), University of Turku, Väisäläntie 20, FI-21500 Piikkiö, Finland
6. European Space Astronomy Centre (ESA/ESAC), Science Operations Department, E-28691 Villanueva de la Cañada, Madrid, Spain
7. Space Research Institute of the Russian Academy of Sciences, Profsoyuznaya Str. 84/32, Moscow 117997, Russia
8. Department of Medical Biophysics, Sunnybrook Hospital M6 623, 2075 Bayview Avenue, Toronto M4N 3M5, Canada