A similar mirror of the same size is illustrated in Ancient Bronze Mirrors from the Shanghai Museum, Shanghai, 2005, pp. 204-5, no. 65, where it is mentioned that similar mirrors have been excavated at E'cheng, Hubei province. Another of slightly larger size (15.5 cm.) is illustrated by T. Nakano et al., Bronze Mirrors from Ancient China: Donald H. Graham Jr. Collection, 1994, pp. 162-3, no. 52. On both of these examples the joined arcs of the outer border are plain. See, also, the very similar mirror in the collection of the Palace Museum, Beijing, illustrated by He Lin, Copper Mirrors - 200 Things You Should Know, Beijing, 2007, p. 60, pl. 30. (Fig. 1)