1. Leiden Observatory, Leiden University, PO Box 9513, NL-2300 RA Leiden, the Netherlands
2. School of Physics, Astronomy and Mathematics, University of Hertfordshire, College Lane, Hatfield AL10 9AB, UK
3. SUPA, Institute for Astronomy, Royal Observatory, Blackford Hill, Edinburgh EH9 3HJ, UK
4. Universität Hamburg, Hamburger Sternwarte, Gojenbergsweg 112, D-21029 Hamburg, Germany
5. Astronomical Observatory, Jagiellonian University, ul. Orla 171, PL-30-244 Kraków, Poland
6. School of Physics and Astronomy, University of Nottingham, Nottingham NG7 2RD, UK
7. CSIRO Astronomy and Space Science, 26 Dick Perry Avenue, Kensington, WA 6151, Australia
8. Astrophysics, University of Oxford, Denys Wilkinson Building, Keble Road, Oxford OX1 3RH, UK
9. Physics and Astronomy Department, University of the Western Cape, Bellville 7535, South Africa
10. Sydney Institute for Astronomy, School of Physics A28, The University of Sydney, NSW 2006, Australia
11. ARC Centre of Excellence for All-Sky Astrophysics (CAASTRO), The University of Sydney, NSW 2006, Australia
12. INAF -- Istituto di Radioastronomia, Via P. Gobetti 101, I-40129 Bologna, Italy
13. GEPI, Observatoire de Paris, CNRS, Universite Paris Diderot, 5 place Jules Janssen, F-92190 Meudon, France
14. Department of Physics and Electronics, Rhodes University, PO Box 94, Grahamstown 6140, South Africa
15. Department of Physics and Astronomy, The Open University, Walton Hall, Milton Keynes MK7 6AA, UK
16. RAL Space, STFC Rutherford Appleton Laboratory, Chilton, Didcot, Oxfordshire OX11 0QX, UK