On combinatorial papers of König and Steinitz (Q1270654)

The author shows that the graph-theoretical theorem of the Hungarian mathematician Dénes König (1884-1944) on the existence of a 1-factor regular bipartite graph of 1914 was already proved twenty years earlier by Ernst Steinitz (1871-1928) in his dissertation: Über die Konstruktion der Configurationen \(n_3\), Universität Breslau. The fact that a graph-theoretical result was proved earlier in the language of configurations is not restricted to the case of the theorem of König and is quite understandable since the combinatorial problems occurred at a time when the language of graph theory was not yet available.