A Construction of Uniquely C4-free colourable Graphs
Gerhard Benadé, Izak Broere, Jason I. Brown · Quaestiones Mathematicae · 1990
An F-free colouring of a graph G is a partition {V1,V2,…,Vn} of the vertex set V(G) of G such that F is not an induced subgraph of G[Vi] for each i. A graph is uniquely F-free colourable if any two .F-free colourings induce the same partition of V(G). We give a constructive proof that uniquely C4-free colourable graphs exist.