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Table 3

2XMMi-DR3 matches in infrared/optical catalogues.

Catalogue Ntotal NP    >    90%

2MASS 557 258
GSC 2.3 741 301
USNO-B1.0 682 264
SDSS-DR7 149 55

Optical 801 329
IR or Optical 829 350



Total number of matches.


Number of matches with individual identification probability higher than 90%.

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