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\iteman{io-port 00716452}
\itemau{Guo, Yubao; Volkmann, Lutz}
\itemti{On complementary cycles in locally semicomplete digraphs.}
\itemso{Discrete Math. 135, No.1-3, 121-127 (1994).}
\itemab
A digraph $D$ is locally semicomplete if for each vertex $x$ in $D$ the subdigraphs induced by the positive and negative neighbor sets of $x$ are both semicomplete. This paper gives the following result about 2- connected locally semicomplete digraphs: Such digraphs do not have their vertex set partitioned by two complementary dicycles if and only if they are 2-diregular and have odd order. From this theorem follow two conjectures of Bang-Jensen giving conditions for a 2-connected local tournament $D$ to have a dicycle $C$ such that $D- V(C)$ is strong.
\itemrv{N.F.Quimpo (Manila)}
\itemcc{}
\itemut{complementary cycles; dicycle cover; locally semicomplete digraphs; tournament; dicycle}
\itemli{doi:10.1016/0012-365X(93)E0099-P}
\end