CCD astrometric observations of Phoebe in 2003–2004R. C. Qiao, Z. H. Tang, K. X. Shen, G. Dourneau, Y. R. Yan, Y. Yu, S. H. Wang and J. R. LiuA&A, 454 1 (2006) 379-383DOI: https://doi.org/10.1051/0004-6361:20054731