On the approximate fixed point property in abstract spaces

Cleon S. Barroso, Ondřej F. K. Kalenda, Pei-Kee Lin

Let $X$ be a Hausdorff topological vector space, $X^{\ast }$ its topological dual and $Z$ a subset of $X^{\ast }$. In this paper, we establish some results concerning the $\sigma (X,Z)$-approximate…