Notes. ^(A)Does not include the X-ray sources that already have a counterpart identified in the first search (in Gaia for optical sources, 2MASS for infrared sources). ^(B)Does not include the X-ray sources that already have a counterpart identified in the first and second search (optical: in Gaia or Pan-STARRS, infrared: in 2MASS and AllWISE). ^(C)Does not include the X-ray sources that already have a counterpart in Gaia, Pan-STARRS, or DES.

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