Flares from small to large: X-ray spectroscopy of Proxima Centauri with XMM-NewtonM. Güdel, M. Audard, F. Reale, S. L. Skinner and J. L. LinskyA&A, 416 2 (2004) 713-732DOI: https://doi.org/10.1051/0004-6361:20031471