Abstract
In 1963, Tibor Gallai [9] asked whether every strongly connected directed graph D is spanned by α directed circuits, where α is the stability of D. We give a proof of this conjecture.
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Bessy, S., Thomassé, S. Spanning a strong digraph by α circuits: A proof of Gallai’s conjecture. Combinatorica 27, 659–667 (2007). https://doi.org/10.1007/s00493-007-2073-3
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DOI: https://doi.org/10.1007/s00493-007-2073-3