Sulfur in the globular clusters 47 Tucanae and NGC 6752 L. Sbordone, M. Limongi, A. Chieffi, E. Caffau, H.-G. Ludwig and P. Bonifacio A&A, 503 1 (2009) 121-127 Published online: 22 June 2009 DOI: 10.1051/0004-6361/200811513