The paper in question included
an appendix, titled “A Wasserman-type theorem for the Rabinowitz action
functional”, where we showed that the Rabinowitz action functional is generically
Morse–Bott and the Morse–Bott manifold is the disjoint union of the energy
hypersurface itself, representing the constant Reeb orbits, and a circle for each Reeb
orbit. The treatment of multiple covered Reeb orbits contained a gap, which is filled
in this note.