We study the joint continuity of mappings of two variables. In particular, we show that for a Baire space $X$, a second countable space $Y$ and a metric space $Z$ a map $f:X\times Y \to Z$ has the Hahn property (i.e. there is a residual subset $A$ of $X$ such that $A\times Y\subseteq C(f)$) if and only if $f$ is locally equvi-cliquish with respect to $y$ and $\{x\in X: f^x \mbox{ is continuous}\}$ is a residual subset of $X$.
@article{372,
title = {Equi-cliquishness and the Hahn property},
journal = {Tatra Mountains Mathematical Publications},
volume = {65},
year = {2016},
doi = {10.2478/tatra.v65i0.372},
language = {EN},
url = {http://dml.mathdoc.fr/item/372}
}
Nesterenko, Vasiľ. Equi-cliquishness and the Hahn property. Tatra Mountains Mathematical Publications, Tome 65 (2016) . doi : 10.2478/tatra.v65i0.372. http://gdmltest.u-ga.fr/item/372/