The masses of young stars: CN as a probe of dynamical masses S. Guilloteau, M. Simon, V. Piétu, E. Di Folco, A. Dutrey, L. Prato and E. Chapillon A&A, 567 (2014) A117 Published online: 24 July 2014 DOI: 10.1051/0004-6361/201423765