Journal Article10.1007/BF01271272
Packing directed circuits
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TL;DR: It is proved that for every digraphG, either G hasn vertex-disjoint directed circuits, or G can be made acyclic by deleting at mostt vertices.
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Abstract: We prove a conjecture of Younger, that for every integern≥0 there exists an integert≥0 such that for every digraphG, eitherG hasn vertex-disjoint directed circuits, orG can be made acyclic by deleting at mostt vertices.
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TL;DR: In this paper, the present problem has been suggested by Miss Esther Klein in connection with the following proposition: "Our present problem is the same problem as the one suggested by the author of this paper."
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TL;DR: The set of pattern graphs for which the directed subgraph homeomorphism problem is NP-complete is characterized and a polynomial time algorithm is given for the remaining cases.
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Packing directed circuits fractionally
TL;DR: There is a set ofO (k logk log k logk) vertices meeting all directed circuits ofG, such that no “fractional” packing of directed circuit ofG has value >k, when every vertex is given “capacity” 1.
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On independent circuits contained in a graph
Paul Erdös,L. Pósa +1 more
TL;DR: In this article, a family of circuits of a graph G is said to be independent if no two of the circuits have a common vertex; it is called edge-independent if none two of them have an edge in common.
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