by @lubinski2016 Sect. 5.1.3]. We verified that imposing ${\mathcal{R}}= 0.6$ we obtain a temperature of $\sim 340$ keV, but with a worse fit ($\Delta {\chi^{2}}= +12$; F-test probability of [$ 4.4 \times 10^{-4}$]{}). [@lubinski2016] also note that the discrepancy could be due to the use of [[*INTEGRAL*]{}]{} data up to 2010 only, and that adding more recent [[*INTEGRAL*]{}]{} data result in a lower value of ${\mathcal{R}}$. Our results are roughly consistent with the temperature being a factor of two or three smaller than the cut-off energy, depending on the optical depth [@pop5548; @poptestingcompt2001]. The difference is actually by a factor of four in [NGC 2110]{}, but since the high-energy turnover of a Comptonisation spectrum is much sharper than an exponential cut-off [e.g. @stern1995; @zdziarski2003; @nied2019], this difference should not be overinterpreted [@poptestingcompt2001].

In both sources, the [Fe K$\alpha$]{} emission line is not accompanied by a significant Compton reflection hump, suggesting that the line originates from Compton-thin material, such as the broad-line region [@kamraj2017; @marinucci2015] or a Compton-thin torus [@borus]. The lack of a Compton hump due to reflection off the accretion disc or an optically thick torus could also indicate that the X-ray corona does not effectively illuminate this surrounding 