1. Mizusawa VLBI Observatory, National Astronomical Observatory of Japan , 2-21-1 Osawa, Mitaka, Tokyo 181-8588, Japan
2. Operation Division, Square Kilometre Array Observatory , Lower Withington, Macclesfield, Cheshire SK11 9FT, UK
3. National Centre for Radio Astrophysics, Tata Institute of Fundamental Research, S. P. Pune University Campus , Ganeshkhind, Pune 411007, India
4. SRON Netherlands Institute for Space Research , Niels Bohrweg 4, 2333 CA Leiden, the Netherlands
5. Department of Physics, Graduate School of Science, Tokyo Metropolitan University , 1-1 Minami-Osawa, Hachioji-shi, Tokyo 192-0397, Japan
6. Leiden Observatory, Leiden University , Niels Bohrweg 2, 2333 CA, Leiden, the Netherlands
7. The Kobayashi-Maskawa Institute for the Origin of Particles and the Universe (KMI), Nagoya University , Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8602, Japan
8. Department of Physical Science, Hiroshima University , 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan
9. Hiroshima Astrophysical Science Center, Hiroshima University , 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan
10. Departure of Physics, Nagoya University , Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8601, Japan
11. Centre for Radio Astronomy Techniques and Technologies, Department of Physics and Electronics, Rhodes University , PO Box 94, Makhanda, 6140, South Africa
12. South African Radio Astronomy Observatory (SARAO) , 2 Fir Street, Black River Park, Observatory, Cape Town 7925, South Africa
13. ASTRON, the Netherlands Institute for Radio Astronomy , Oude Hoogeveensedijk 4, 7991 PD Dwingeloo, the Netherlands
14. Leiden Observatory, Leiden University , PO Box 9513, NL-2300 RA Leiden, the Netherlands
15. Department of Physics, Yamagata University , 1-4-12 Kojirakawa-machi, Yamagata, Yamagata 990-8560, Japan