1. South African Radio Astronomy Observatory, 2 Fir Street, Black River Park, Observatory, Cape Town 7925, South Africa
2. Department of Physics and Electronics, Rhodes University, PO Box 94, Makhanda 6140, South Africa
3. Argelander-Institut für Astronomie, Auf dem Hügel 71, D-53121 Bonn, Germany
4. Department of Physics, University of Pretoria, Hatfield, Pretoria 0028, South Africa
5. Ruhr University Bochum, Faculty of Physics and Astronomy, Astronomical Institute, D-44780 Bochum, Germany
6. National Radio Astronomy Observatory, 1003 Lopezville Rd, Socorro, NM 87801, USA
7. Kavli Institute for Astronomy and Astrophysics, Peking University, Beijing 100871, China
8. Department of Astrophysics/IMAPP, Radboud University, PO 9010, NL-6500 GL, Nijmegen, the Netherlands
9. Inter-University Institute for Data Intensive Astronomy, Department of Astronomy, University of Cape Town, Private Bag X3, Rondebosch 7701, South Africa
10. South African Astronomical Observatory, PO Box 9, 7935 Observatory, South Africa
11. INAF - Osservatorio Astronomico di Cagliari, Via della Scienza 5, I-09047 Selargius (CA), Italy
12. Netherlands Institute for Radio Astronomy (ASTRON), Postbus 2, NL-7990 AA Dwingeloo, the Netherlands
13. Department of Astronomy, University of Cape Town, Private Bag X3, Rondebosch 7701, South Africa
14. Kapteyn Astronomical Institute, University of Groningen, Postbus 800, NL-9700 AV Groningen, the Netherlands
15. Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA) and Department of Physics and Astronomy, Northwestern University, 1800 Sherman Ave, Evanston, IL 60201, USA
16. IAU-Office For Astronomy for Development, PO Box 9, 7935 Observatory, South Africa
17. Leiden Observatory, Leiden University, PO Box 9513, NL-2300 RA Leiden, the Netherlands
18. Centre for Space Research, North-West University, Potchefstroom campus, Private Bag X6001, Potchefstroom 2520, South Africa
19. Department of Physics and Astronomy, University of the Western Cape, Bellville, South Africa