Locations of v¡ resonance centers and the corresponding boundaries of the libration domain of the partial normal form ${\overline{H}}_n^{*}$ with n = 0,1,…, 4. The resonance center at ψ₂ = 0 (ψ₂ = π) of the ideal resonance model ${\overline{H}}_0^{*}$ is presented as a solid red (blue) curve in each frame. The boundaries of the libration domains that embrace the curves of center at Ψ₂ = 0 (Ψ₂ = π) are presented as pink (light blue) curves. The resonance structures of the partial normal form ${\overline{H}}_n^{*}$ with n = 1,…, 4 are presented as dashed curves in frames a-d. The vertical gray curves are level curves of I₁, which approximates the level curves of J₁, along which the v₅ libration follows. In frame c, the yellow dot marks the pseudo-proper elements of the flow of ${\overline{H}}_{\text{Schubart }}$ in frame c of Fig. E.1.