a Mathematical Institute, Czech Academy of Science, ?itná 25, 115 67 Praha 1, Czech Republic b Department of Mathematical Analysis, Charles University, Sokolovská 83, 186 75 Praha 8, Czech Republic
Abstract:
A new rotundity property of Day's norm on c0(Γ) is introduced. This property provides in particular a renorming characterization of the class of all reflexive Banach spaces.