Before revision:  We introduce twelve sets of Wang tiles \{\mathcal{T_{i}\}_{1\leq i\leq 12} together with their associated Wang shifts \{i\}_{1\leq i\leq 12}.
After revision:  We introduce twelve sets of Wang tiles _{i}\}_{1\leq i\leq 12} together with their associated Wang shifts \{i\}_{1\leq i\leq 12}.