“…F A Comment on the Gauge Theory of Gravitation of References [19] and [44] In footnote 1 we recalled that in GRT a gravitational field is defined by an equivalence class of pentuples, where (M, g, D, τ g , ↑) and (M ′ , g ′ , D ′ , τ ′ g , ↑ ′ ) are said equivalent if there is a diffeomorphism f : M → M ′ , such that g ′ = f * g, D ′ = f * D, τ ′ g = f * τ g , ↑ ′ = f * ↑, (where f * here denotes the pullback mapping). For more details, see, e.g., [81,74,77]. Moreover, in GRT when one is studying the coupling of the matter fields, represented, say by some sections of the exterior algebra bundle 66 ψ 1,..., ψ n , which satisfy certain coupled differential equations (the equations of motion 67 ), two models {(M, g, D, τ g , ↑), ψ 1,..., ψ n } and (M ′ , g ′ , D ′ , τ ′ g , ↑ ′ ), ψ ′ 1,..., ψ ′ n } are said to be dynamically equivalent iff there is a diffeomorphism h : M → M ′ , such that (M, g, D, τ g , ↑) and (M ′ , g ′ , D ′ , τ ′ g , ↑ ′ ) and moreover ψ ′ i = f * ψ i , i = 1, ..., n. This kind of equivalence is not a particularity of GRT, it is an obvious mathematical requirement that any theory formulated with tensor fields living in an arbitrary manifold must satisfy 68 .…”