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Messina, S.; Guinan, E. F. (tháng 10 năm 2003), “Magnetic activity of six young solar analogues II. Surface Differential Rotation from long-term photometry”, Astronomy and Astrophysics, 409: 1017–1030, Bibcode:2003A&A...409.1017M, doi:10.1051/0004-6361:20031161.