We show that the basic results on the paper referred in the title [J. Phys. A: Math. Gen. v. 35 (2002) 5333-5345], concerning the derivation of the Ermakov invariant from Noether symmetry methods, are not new.
Construction of SU(3) irreps in canonical SO(3)-coupled bases
Construction of potential systems for systems of PDEs with multi-dimensional spaces of conservation laws
Construction of Quantum Field Theories with Factorizing S-Matrices
