Magnetic activity and differential rotation in the very young star KIC 8429280 A. Frasca, H.-E. Fröhlich, A. Bonanno, G. Catanzaro, K. Biazzo and J. Molenda-Żakowicz A&A, 532 (2011) A81 Published online: 26 July 2011 DOI: 10.1051/0004-6361/201116980