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The issue of "Commemorative Stamps for Modern Chinese Scientists (IX)" is the ninth set of commemorative stamps for modern Chinese scientists in China issued after 34 years after the first set of "Commemorative Stamps for Modern Chinese Scientists (I)" was issued by 1988.

(4- 1)J Liu Dongsheng face value1.9.8 million pieces in 20 yuan.

(4-2)J becomes Jia Kai, with a face value of 1.20 yuan, 9.8 million pieces.

(4-3)J Wu Wenjun face value1.9.8 million pieces in 20 yuan.

(4-4)J Yuan Longping, par value 1.20 yuan, 9.8 million pieces.