Comparison of Ω_R-Ω_z frequencies determined by several different methods. The first row shows the frequencies determined using the action-angle method (in grey), with three selected stars (A, B, and C) indicated by coloured star symbols. These three stars are also depicted in the following two rows, which show the SuperFreq- and NAFF-determined frequencies, respectively. Star A (blue) is determined to be on the Ω_z/Ω_R = 0.7 branch both for the action-angle frequencies and by NAFF. However, SuperFreq disagrees, placing this star on the 1:2 resonance. Star B (orange) is on the Ω_z/Ω_R = 0.7 branch for the action-angle frequencies only, but NAFF and SuperFreq place this star on the 1:2 resonance. Finally, star C (green) is on the Ω_z/Ω_R = 0.7 branch in all three methods.