Abundances of C, N, O in slightly evolved stars in the globular clusters NGC 6397, NGC 6752 and 47 TucE. Carretta, R. G. Gratton, S. Lucatello, A. Bragaglia and P. BonifacioA&A, 433 2 (2005) 597-611DOI: https://doi.org/10.1051/0004-6361:20041892
