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\iteman{io-port 01060754}
\itemau{Niessen, Th.}
\itemti{A characterization of graphs having all $(g,f)$-factors.}
\itemso{J. Comb. Theory, Ser. B 72, No.1, 152-156 (1998).}
\itemab
Let $G$ be a graph with vertex set $V$ and let $g,f:V\to\bbfZ^+$. We say that $G$ has all $(g,f)$-factors, if $G$ has an $h$-factor for every $h:V\to\bbfZ^+$ such that $g(v)\leq h(v)\leq f(v)$ for every $v\in V$ and at least one such $h$ exists. We derive from Tutte's $f$-factor theorem a similar characterization for the property of having all $(g,f)$-factors. An analogous result for parity factors is presented also.
\itemrv{Th.Niessen (Aachen)}
\itemcc{}
\itemut{characterization; $(g,f)$-factors; parity factors}
\itemli{doi:10.1006/jctb.1997.1797}
\end