Time delay of SBS 0909+532 A. Ullán, L. J. Goicoechea, A. P. Zheleznyak, E. Koptelova, V. V. Bruevich, T. Akhunov and O. Burkhonov A&A, 452 1 (2006) 25-35 Published online: 17 May 2006 DOI: 10.1051/0004-6361:20054283
