A timeline for massive star-forming regions via combined observation of o-H2D+ and N2D+A. Giannetti, S. Bovino, P. Caselli, S. Leurini, D. R. G. Schleicher, B. Körtgen, K. M. Menten, T. Pillai and F. WyrowskiA&A, 621 (2019) L7DOI: https://doi.org/10.1051/0004-6361/201834602
