Spectroscopic analysis of the two subgiant branches of the globular cluster NGC 1851R. G. Gratton, S. Villanova, S. Lucatello, A. Sollima, D. Geisler, E. Carretta, S. Cassisi and A. BragagliaA&A, 544 (2012) A12DOI: https://doi.org/10.1051/0004-6361/201219276