  Nineteen classical superintegrable systems in two-dimensional non-Euclidean
spaces are shown to possess hidden symmetries leading to their linearization.
They are the two Perlick systems [A. Ballesteros, A. Enciso, F.J. Herranz and
O. Ragnisco, Class. Quantum Grav. 25, 165005 (2008)], the Taub-NUT system [A.
Ballesteros, A. Enciso, F.J. Herranz, O. Ragnisco, and D. Riglioni, SIGMA 7,
048 (2011)], and all the seventeen superintegrable systems for the four types
of Darboux spaces as determined in [E.G. Kalnins, J.M. Kress, W. Miller, P.
Winternitz, J. Math. Phys. 44, 5811--5848 (2003)].
