We give examples of results on composition operators connected with lens maps. The first two concern the approximation numbers of those operators acting on the usual Hardy space H2. The last ones are connected with ...

We produce several situations where some natural subspaces of classical Banach spaces of functions over a compact abelian group contain the space c0.

We give a criterion of weak compactness for the operators on the Morse-Transue space MΨ , the subspace of the Orlicz space LΨ generated by L∞.

We give new proofs that some Banach spaces have Peczynski's property (V)