NGC 6334 and NGC 6357 - Insights from spectroscopy of their OB star populations D. Russeil, C. Adami, J. C. Bouret, A. Hervé, Q. A. Parker, A. Zavagno and F. Motte A&A, 607 (2017) A86 Published online: 20 November 2017 DOI: 10.1051/0004-6361/201629870