A giant step: from milli- to micro-arcsecond astrometry : proceedings of the 248th symposium of the International Astronomical Union held in Shanghai, China : October 15-19, 2007. : IAU symposium no. 248 : IAUS248 : IAU S248 : Oct 2007, Shanghai, China.
A giant step: from milli- to micro-arcsecond astrometry : proceedings of the International Astronomical Union : IAU symposium 248 : 15-19 October 2007, Shanghai, China