Chemical evolution in the early phases of massive star formation. IT. Gerner, H. Beuther, D. Semenov, H. Linz, T. Vasyunina, S. Bihr, Y. L. Shirley and Th. HenningA&A, 563 (2014) A97DOI: https://doi.org/10.1051/0004-6361/201322541