Correlation between observed frequency ν_QPO and the Kepler frequency at the transition radius ν_K(r_J) (top), as well as the residuals defined as the ratio between the best weighted fit (in red) and the data (bottom). In their own colors, different types of quasi-periodic oscillations: Type A in light-yellow, Type B in cyan, Type C in dark-blue. In red the weighed linear fit considering only Type C LFQPOs, ν_QPO = (10 ± 3) × 10⁻³ ⋅ ν_K(r_J)^{0.96 ± 0.04}, in black the ν_QPO = ν_K(r_J)/100 line.