1. Jodrell Bank Centre for Astrophysics, Department of Physics and Astronomy, School of Natural Sciences, The University of Manchester, Alan Turing building, Oxford Road, Manchester M13 9PL, UK
2. Cahill Centre for Astronomy and Astrophysics, California Institute of Technology, Pasadena, CA 91125, USA
3. Instituto de Astrofísica de Canarias, E-38200 La Laguna, Tenerife, Canary Islands, Spain
4. Departamento de Astrofísica, Universidad de La Laguna (ULL), E-38206 La Laguna, Tenerife, Spain
5. Sub-department of Astrophysics, University of Oxford, Denys Wilkinson Building, Keble Road, Oxford OX1 3RH, UK
6. Astrophysics Group, Cavendish Laboratory, University of Cambridge, J.J. Thomson Avenue, Cambridge CB3 0HE, UK
7. Kavli Institute for Cosmology, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK
8. Instituto de Física de Cantabria (CSIC-Universidad de Cantabria), Avda. de los Castros s/n, E-39005 Santander, Spain
9. Department of Physics, McGill University, 3600 Rue University, Montréal, QC H3A 2T8, Canada
10. School of Mathematics, Statistics & Computer Science, University of KwaZulu-Natal, Westville Campus, Private Bag X54001, Durban 4000, South Africa
11. Department of Physics and Electronics, Rhodes University, Grahamstown 6139, South Africa
12. South African Radio Astronomy Observatory, 2 Fir Road, Observatory, Cape Town 7925, South Africa
13. Consejo Superior de Investigaciones Científicas, C. Serrano, 117, 28006 Madrid, Spain
14. Space Science Data Center – Agenzia Spaziale Italiana, Via del Politecnico snc, I-00133 Rome, Italy
15. Istituto Nazionale di Fisica Nucleare, Sezione di Roma 2, Via della Ricerca Scientifica 1, I-00133 Rome, Italy
16. School of Chemistry & Physics, University of KwaZulu-Natal, Westville Campus, Private Bag X54001, Durban 4000, South Africa