1. Astrophysics Research Institute, Liverpool John Moores University, IC2 Liverpool Science Park, Liverpool L3 5RF, UK
2. Centre for Astronomy, School of Physics, National University of Ireland Galway, H91 TK33, University Road, Galway, Ireland
3. National Observatory Athens, Inst Astron Astrophys Space Applicat & Remote Sen, GR-15236 Athens, Greece
4. Instituto de Matemática, Estatística e Física, Universidade Federal do Rio Grande, Rio Grande 96203-900, Brazil
5. Department of Physics, Lancaster University, Lancaster LA1 4YB, UK
6. Finnish Centre for Astronomy with ESO (FINCA), Quantum, Vesilinnantie 5, University of Turku, 20014 Turku, Finland
7. Department of Physics and Astronomy, University of Turku, 20014 Turku, Finland
8. Department of Physics and Institute of Theoretical and Computational Physics, University of Crete, 71003 Heraklion, Crete, Greece
9. Institute of Astrophysics, Foundation for Research and Technology-Hellas, 71110 Heraklion, Crete, Greece
10. Department of Physics, University of Athens, GR-15784, Athens, Greece