Identifying two groups of massive stars aligned in the l ~ 38° Galactic direction S. Ramírez Alegría, A. Herrero, K. Rübke, A. Marín-Franch, M. García and J. Borissova A&A, 614 (2018) A116 Published online: 22 June 2018 DOI: 10.1051/0004-6361/201731720