QPO frequency as a function of luminosity. Purple and orange represent the ∼2 mHz QPO and ∼1 mHz QPO, respectively. The inverted triangles correspond to data from Roy et al. (2019), while the squares represent the results of this study. We excluded the ∼2 mHz data point from Roy et al. (2019) in cases where ∼2 mHz and ∼1 mHz QPOs were detected simultaneously in a single power spectrum, as they likely represent harmonic components.