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{\bf Lutz Volkmann}
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{\bf A Short Proof of a Theorem of Kano and Yu on Factors in Regular Graphs}
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In this note we present a short proof of the following result, which
is a slight extension of a nice 2005 theorem by Kano and Yu. Let
$e$ be an edge of an $r$-regular graph $G$. If $G$ has a 1-factor
containing $e$ and a 1-factor avoiding $e$, then $G$ has a $k$-factor
containing $e$ and a $k$-factor avoiding $e$ for every
$k\in\{1,2,\ldots,r-1\}$.
\bye