The clique corona operation and greedoids

S is a local maximum stable set of G, and we write S∈ ∈Ψ(G), if S is a stable set of maximum size in the subgraph induced by S ∪ N(S), where N(S) is the neighborhood of S. It is known that Ψ(G) is a greedoid for every forest G, [10]. Bipartite graphs and triangle-free graphs, whose families of local maximum stable sets form greedoids were characterized in [11] and [12], respectively. The clique corona is the graph G∈=∈H∈? o {H ₁,H ₂,...,H _n } obtained by joining each vertex v _k of the graph H with the vertices of some clique H _k , respectively. In this paper we demonstrate that if G is a clique corona, then Ψ(G) forms a greedoid on its vertex set.