Z_2× Z_2-cordial cycle-free hypergraphs
Sylwia Cichacz, Agnieszka Görlich, Zsolt Tuza · Discussiones Mathematicae Graph Theory · 2019
Hovey introduced A-cordial labelings as a generalization of cordial and harmonious labelings If A is an Abelian group, then a labeling f : V (G) A of the vertices of some graph G induces an edge labeling on G; the edge uv receives the label f (u) + f (v). A graph G is A-cordial if there is a vertexlabeling such that (1) the vertex label classes differ in size by at most one and (2) the induced edge label classes differ in size by at most one.