0)  \(0) at (0,0) ; (0) at (0.0,0) [$\mathcal D_0$ ; $\mathcal D_0$]{}; (0) at (0.0,-0.0) [$\mathcal D_0$ ; $\mathcal D_0$ ; $\mathcal D_0$]{}; (0) - (0,0) - (0); (0) - (0,0) |- (0);  ; (c0b) at (00,-0)  \(0) at (0,0) ; (0) at (0.0,0) [${\mathcal D_0^*}$ ; ${\mathcal D_0^*}$ ; ${\mathcal D_0^{\Box}}$]{}; (0) at (0.0,-0.0) [${\mathcal D_0^*}$ ; ${\mathcal D_0^{\Box}}$ ; ${\mathcal D_0^{\Box}}$]{}; (0) - (0,0) - (0); (0) - (0,0) |- (0);  ; (c0) at (0.0,-0.0)  \(0) at (0,0) ; (0) at (0.0,0) [$\mathcal D_0$ ; $\mathcal D_0$ ; $\mathcal D_0$]{}; (0) - (0,0) - (0); 