“…) is a solution of (3.26) in the sense of distributions, then ϕ ∈ H n per ([0, L]), for all n ∈ N. This result can be proved by an iteration method and is a consequence of the fact that ϕ ∈ 1 (see [19,Proposition 3.1]). In particular, using the previous theorem, we have that ϕ (ω,W ) → ϕ (ω0,0) , as (ω, W ) → (ω 0 , 0), in L ∞ per ([0, L]).…”