Affiliation: | (1) Observatoire de Paris -, Université Paris, 7, DAEC, F-92190 Meudon, France;(2) Dept. of Physics, University of Crete, GR-71003 Heraklion, Greece;(3) Osservatorio Astronomico di Torino, Strada dell'Osservatorio 20, I-10025 Pino Torinese, Italy |