altered by absorption, however we assumed ${N_{\textrm{H}}}= {4 \times 10^{22}}$ [cm$^{-2}$]{} [@marinucci2015].

Fitting the data with a power law, we obtained a statistically good fit (${\chi^{2}/\textrm{dof}}=9/10$) with a hint of a curvature above 120 keV (Fig. \[fig:ratios2110\], first panel). We also tested three other models, as done for [NGC 4388]{}, namely: [[pexrav]{}]{} with $\mathcal{R} = 0.5$, a cut-off power law and [[compps]{}]{}. We obtained the same improvement in terms of ${\chi^{2}}$ for all the three models (${\chi^{2}/\textrm{dof}}=5/9$; see Fig. \[fig:ratios2110\]). Finally, we extrapolated the best-fitting cut-off power law down to 3 keV and compared it with the [[*XMM–Newton*]{}]{} and [[*NuSTAR*]{}]{} spectra (Fig. \[fig:extrap\_2110\]). Despite the significant flux variability in the 3–79 keV band, there is no strong evidence of significant spectral variability among the different observations.

![\[fig:ratios2110\] Residuals of fits of IBIS spectrum with different models. Upper panel: simple power law. Second panel: power law plus reflection ([[pexrav]{}]{}). Third panel: exponentially cut-off power law. Lower panel: thermal Comptonisation model ([[compps]{}]{}). ](ratios_2110){width="\columnwidth"}

![\[fig:extrap\_2110\] Upper panel: [[*XMM–Newton*]{}]{} and [[*NuSTAR*]{}]{} spectra of NGC 2110 with the cut-off power law that best fits IBIS. Lower panel: data/model ratio. Only [[*NuSTAR*]{}]{}’s FPMA data are shown for clarity. The data were binned for plotting purposes.](extrap_2110){width="\columnwidth"}

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