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A digraph D=(V,A) is cycle-connected if every pair of vertices are contained in a directed cycle. Recently, Hubenko[Discrete Math. 308(2008) 1018-1024] proved that every cycle-connected bipartite tournament D has a universal arc, i.e.,an arc such that for every vertex there is a directed cycle in D containing both e and x. In this thesis, we refine the previous result and show that if D is a cycle-connected bipartite tournament with min then every longest cycle of C contains at least 4k-4 universal arcs, where is an integer, and are the minimum in-degree and out-degree of verices in D, respectively.
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