Affiliation: | (1) Astronomical Observatory, Kiev National University, Observatorna ul., Kiev, 304053, Ukraine;(2) Special Astrophysical Observatory, Russian Academy of Sciences, Nizhniĭ Arkhyz, 357147, Karachaĭ-Cherkessian Republic, Russia;(3) Max Planck Institut für Radioastronomie, Auf dem Hügel 69, D-53121 Bonn, Germany |