The HARPS search for southern extra-solar planets - XIII. A planetary system with 3 super-Earths (4.2, 6.9, and 9.2 M)M. Mayor, S. Udry, C. Lovis, F. Pepe, D. Queloz, W. Benz, J.-L. Bertaux, F. Bouchy, C. Mordasini and D. SegransanA&A, 493 2 (2009) 639-644DOI: https://doi.org/10.1051/0004-6361:200810451
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