“…either they are all clique divergent or they are all clique convergent) but this technique does not allow us to determine whether this behavior is convergent or divergent. C n (1, 2, 4) does not have any local cutpoints nor dominated vertices, so the corresponding techniques [8,9] do not work here. Also, C becomes clique convergent when we remove any vertex (K 4 (C −{0}) is already a Helly graph), this implies that C does not have any clique divergent retract (other than itself) hence retractions [20,21] can not be used here.…”