Institution: | a IRMAR UMR 6625, Université de Rennes 1, Campus de Beaulieu, 35042 Rennes Cedex, France b 1 Chemin du Chateau, 76 430 Les Trois Pierres, France c Institute of Astronomy, University of Zielona Góra, Licealna 9, PL-65-417 Zielona Góra, Poland d Toruń Centre for Astronomy, N. Copernicus University, Gagarina 11, PL-87-100 Toruń, Poland |