1. Konkoly Observatory, Research Centre for Astronomy and Earth Sciences, Eötvös Loránd Research Network (ELKH), Hungarian Academy of Sciences , Konkoly-Thege Miklós út 15–17, H-1121 Budapest , Hungary
2. CSFK, MTA Centre of Excellence , Konkoly Thege Miklós út 15–17, H-1121 Budapest , Hungary
3. Department of Astronomy, California Institute of Technology , Pasadena, CA 91125 , USA
4. Institute of Physics, ELTE Eötvös Loránd University , Pázmány Péter sétány 1/A, H-1117 Budapest , Hungary
5. Max Planck Institute for Astronomy , Kónigstuhl 17, D-69117 Heidelberg , Germany
6. INAF-Osservatorio Astronomico di Roma , via di Frascati 33, I-00040 Monte Porzio Catone , Italy
7. Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology , Cambridge, MA 02139 , USA
8. Department of Theoretical Physics and Astrophysics, Masaryk University , Kotlářská 2, Brno, CZ-611 37 , Czech Republic
9. Department of Statistics, University of the Western Cape , Private Bag X17, Bellville, 7535 Cape , South Africa
10. INAF-Osservatorio Astronomico di Capodimonte , via Moiariello 16, I-80131 Napoli , Italy
11. Centre for Astrophysics, University of Hertfordshire , College Lane, Hatfield AL10 9AB , UK
12. Astronomical Observatory, University of Warsaw , Al. Ujazdowskie 4, PL-00-478 Warszawa , Poland
13. Max-Planck-Institut für Radioastronomie , Auf dem Hügel 69, D-53121 Bonn , Germany
14. Scottish Universities Physics Alliance (SUPA), School of Physics and Astronomy, University of St Andrews , North Haugh, St Andrews KY16 9SS , UK