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MAD family; Vietoris topology; continuous selection
We show that if $\Cal A$ is an uncountable AD (almost disjoint) family of subsets of $\omega$ then the space $\Psi(\Cal A)$ does not admit a continuous selection; moreover, if $\Cal A$ is maximal then $\Psi(\Cal A)$ does not even admit a continuous selection on pairs, answering thus questions of T. Nogura.
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