You are so lucky, I just found it
The surname of Twenty Paintings: Luo Yanzhong Shi Landang Dou Huaiji
20-3-2, 20-1-4, 20-3-10, 20-1-10, 20-3-12, 20-1-12, 20-3-22, 20-1-14, 20-12-20, 20- 9-23, 20-4-7, 20-13-2, 20-11-2, 20-4-17, 20-13-12, 20-11-4, 20-9-2, 20-19- 2, 20-11-14, 20-9-12 20-12-20．