Totally unimodular Leontief directed hypergraphs
A Leontief directed hypergraph is a generalization of a directed graph, where arcs have multiple (or no) tails and at most one head. The authors define a subclass of Leontief directed hypergraphs via forbidden odd pseudocycles. They show that the vertex-hyperarc incidence matrices of the hypergraphs in this subclass are totally unimodular. In addition, they present examples of Leontief directed hypergraphs that are graphic, cographic, and neither graphic nor cographic.
scientific article; zbMATH DE number 826711