The Ca II Infrared Triplet as a stellar activity diagnostic - I. Non-LTE photospheric profiles and definition of the R indicatorV. Andretta, I. Busà, M. T. Gomez and L. TerranegraA&A, 430 2 (2005) 669-677DOI: https://doi.org/10.1051/0004-6361:20041745
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