“…Proof: (1) While the point a 0 ∈ SC 3,6, * 18 has the smallest open set N * 18 (a 0 , 2), each point x ∈ SC 3,6 18 in (a), (b) and (c) of Figure 2 has the smallest open sets in N * 18 (x, 1) ⊂ SC 3,6 18 in (a), (b) and (c) of Figure 2, respectively. This implies that SC 3,6, * 18 cannot be KD-(18, 18)-, K-18-and 18-homeomorphic to each of the spaces SC 3,6 18 in (a), (b) and (c) of Figure 2 because there cannot be KD-18-, K-18-and 18-continuous maps from SC 3,6, * 18 onto each of the spaces SC 3,6 18 in (a), (b) and (c) of Figure 2.…”