“…(A2) Sufficiently smooth solutions (ρ, w) and (ρ, ŵ) to the system (1)-( 5) exist for parameters 0 ≤ ε, ε ≤ ε and 0 < γ ≤ γ, γ ≤ γ with γ, γ constant, which satisfy ρ ≤ ρ, ρ ≤ ρ and − w ≤ w, ŵ ≤ w. (8) Conditions (A1) and (A2) imply uniform bounds for P and its derivatives and ensure that the flow is subsonic; we refer to [6] for details. Under these conditions, we will show the following stability result: Let (ρ, w) and (ρ, ŵ) be sufficiently regular solutions of (1)- (3) with parameters ε, γ and ε, γ, and boundary values ĥ∂ and h ∂ as described in (6). Then…”