The VLT-FLAMES Tarantula Survey: XXV. Surface nitrogen abundances of O-type giants and supergiants (Astronomy and Astrophysics, 2017)

(untitled) - Grin, N; Ramírez-Agudelo, O; de Koter, A; Sana, H; Puls, J; Brott, I; Crowther, P; Dufton, P; Evans, C; Gräfener, G; Herrero, A; Langer, N; et al.