2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/196185We argue that the obstacles to having a first-order formalism for odd-derivative actions presented in a pedagogical note by Deser are based on examples which are not first-order forms of the original actions. The general derivation of an equivalent first-order form of the original second-order action is illustrated using the example of topologically massive electrodynamics (TME). The correct first-order formulations of the TME model keep intact the gauge invariance presented in its second-order form demonstrating that the gauge invariance is not lost in the Ostrogradsky process.6 pages, references are addedHigh Energy Physics - TheoryGeneral Relativity and Quantum Cosmologytext