Affiliation: | CRAL-Observatoire de Lyon, 9 avenue Charles André69561 Saint Genis Laval cedex, France;Special Astrophysical Observatory, Nizhnij Arkhyz Karachai-Cirkasia 357 147, Russia;Blackett Laboratory Optics Section, Imperial College, London SW7 2BZ;Instituto de Astrofisica, c/Via Lactea s/n 38200 La Laguna, Tenerife, Spain |