2 citations · 2 across the 1 of their papers we have counts for
1 paper
M. J. Page, I. Lehmann, Th. Boller +15
We present optical and X-ray data for a sample of serendipitous XMM-Newton sources that are selected to have 0.5-2 keV vs 2-4.5 keV X-ray hardness ratios which are harder than the…