**Table 2:** Number of quasars cross-identified between the recent catalog of Véron Cetty & Véron (2003) and two categories of catalogs used in the construction of the ICRF: the combination of the defining, candidate and other sources of Table 1, with 608 sources, and its extension, the ICRF-Ext.2 catalog containing 717 sources. Two different angular thresholds have been chosen for the cross-identification: 2'' and 4''. The rms concern the differences in the positions, in arcsecond, for the cross-identified sources.
Catalog	Threshold	ICRF	ICRF-Ext.2
VV2003	('')	(3 categories)
Quasars	4	361/608	403/717
		(59.4%)	(56.2%)
rms ('') $\alpha$ / $\delta$		0.84/0.73	0.84/0.72
BL LAC	4	63/608	66/717
		(10.4%)	(9.2%)
rms ('') $\alpha$ / $\delta$		0.76/0.55	0.77/0.55
Active galaxies	4	50/608	69/717
		(8.2%)	(9.6%)
rms ('') $\alpha$ / $\delta$		0.90/0.64	0.93/0.82
All objects	4	474/608	538/717
rms ('') $\alpha$ / $\delta$		(77.9%)	(75.0%)
Quasars	2	349/608	390/717
		(57.4%)	(5.4%)
rms ('') $\alpha$ / $\delta$		0.77/0.67	0.77/0.65
BL LAC	2	63/608	66/717
		(10.4%)	(9.2%)
rms ('') $\alpha$ / $\delta$		0.76/0.55	0.77/0.55
Active galaxies	2	48/608	64/717
		(7.8%)	(8.9%)
rms ('') $\alpha$ / $\delta$		0.78/0.64	0.75/0.67
All objects	2	460/608	520/717
		(75.7%)	(72.5%)
rms ('') $\alpha$ / $\delta$

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