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{\bf Alexandr Kostochka}
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{\bf On a Theorem of Erd\H os, Rubin, and Taylor on
Choosability of Complete Bipartite Graphs}
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Erd\H os, Rubin, and Taylor found a nice correspondence
between the minimum order of a complete bipartite graph that is not
$r$-choosable and the minimum number of edges
in an $r$-uniform hypergraph that is not $2$-colorable
(in the ordinary sense). In this note we use
their ideas to derive similar correspondences
for complete $k$-partite graphs and
complete $k$-uniform $k$-partite hypergraphs.

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