High resolution optical spectroscopy of the N2-rich comet C/2016 R2 (PanSTARRS) C. Opitom, D. Hutsemékers, E. Jehin, P. Rousselot, F. J. Pozuelos, J. Manfroid, Y. Moulane, M. Gillon and Z. Benkhaldoun A&A, 624 (2019) A64 Published online: 11 April 2019 DOI: 10.1051/0004-6361/201834357