More proofs of menger's theorem
C. St. J. A. Nash‐Williams, W. T. Tutte · Journal of Graph Theory · 1977
Abstract Four ways of proving Menger's Theorem by induction are described. Two of them involve showing that the theorem holds for a finite undirected graph G if it holds for the graphs obtained from G by deleting and contracting the same edge. The other two prove the directed version of Menger's Theorem to be true for a finite digraph D if it is true for a digraph obtained by deleting an edge from D.