Colouring planar mixed hypergraphs
The authors show that maximal planar bi-hypergraphs are 2-colorable. They also find formulas for their chromatic polynomial and chromatic spectrum in terms of 2-factors in the dual. Furthermore, they show that their chromatic spectrum is gap-free and give an estimate on the number of colors in a coloring.
scientific article; zbMATH DE number 1549888