The chemical structure of the Class 0 protostellar envelope NGC 1333 IRAS 4A E. Koumpia, D. A. Semenov, F. F. S. van der Tak, A. C. A. Boogert and E. Caux A&A, 603 (2017) A88 Published online: 11 July 2017 DOI: 10.1051/0004-6361/201630160