1. Astrophysikalisches Institut und Universitätssternwarte, Friedrich-Schiller-Universität Jena , Schillergäßchen 2-3, D-07745 Jena, Germany
2. Institute of Astronomy, University of Cambridge , Madingley Road, Cambridge CB3 0HA, UK
3. Joint ALMA Observatory , Alonso de Córdova 3107, VA 763-0355, Santiago, Chile
4. National Radio Astronomy Observatory , 520 Edgemont Road, Charlottesville, VA 22903-2475, USA
5. Observatoire de Paris, PSL Research University, CNRS, Sorbonne Universités , UPMC, 61 Av. de l’Observatoire, F-75014 Paris, France
6. Konkoly Observatory, Research Centre for Astronomy and Earth Sciences, Eötvös Loránd Research Network (ELKH) , Konkoly-Thege Miklós út 15-17, 1121 Budapest, Hungary
7. Steward Observatory, Department of Astronomy, University of Arizona , 933 N. Cherry Ave, Tucson, AZ 85721, USA
8. Instituto Nacional de Astrofísica Optica y Electrónica Luis Enrique Erro #1 , CP 72840 Tonantzintla, Puebla, México