ABSTRACT
In this appendix we collect all the function spaces that we consider in this book.
Given an open set Ω ⊂ RN (even Ω = RN ), we denote by Cb(Ω) (resp. Cb(Ω)) the space of bounded and continuous functions f : Ω → R (resp. f : Ω → R) and we endow it with the sup-norm, i.e.,
||f ||∞ = sup x∈Ω
|f(x)|, f ∈ Cb(Ω) (resp. f ∈ Cb(Ω)).