Yan Jingshu poses for photo in front of the ancient book restoration center of Zhejiang Library in Hangzhou, east China's Zhejiang Province, May 23, 2018. Yan, 55, has worked in the national level ancient book restoration center of the library for 38 years. She and her colleagues collected more than 200 types of paper to restore ancient books. (Xinhua/Weng Xinyang)
Yan Jingshu restores an ancient book at Zhejiang Library in Hangzhou, east China's Zhejiang Province, May 23, 2018. Yan, 55, has worked in the national level ancient book restoration center of the library for 38 years. She and her colleagues collected more than 200 types of paper to restore ancient books. (Xinhua/Weng Xinyang)
Yan Jingshu shows an ancient book under restoration at Zhejiang Library in Hangzhou, east China's Zhejiang Province, May 23, 2018. Yan, 55, has worked in the national level ancient book restoration center of the library for 38 years. She and her colleagues collected more than 200 types of paper to restore ancient books. (Xinhua/Weng Xinyang)
Yan Jingshu restores an ancient book at Zhejiang Library in Hangzhou, east China's Zhejiang Province, May 23, 2018. Yan, 55, has worked in the national level ancient book restoration center of the library for 38 years. She and her colleagues collected more than 200 types of paper to restore ancient books. (Xinhua/Weng Xinyang)
Yan Jingshu planishes an ancient book after restoration at Zhejiang Library in Hangzhou, east China's Zhejiang Province, May 23, 2018. Yan, 55, has worked in the national level ancient book restoration center of the library for 38 years. She and her colleagues collected more than 200 types of paper to restore ancient books. (Xinhua/Weng Xinyang)
Yan Jingshu planishes an ancient book after restoration at Zhejiang Library in Hangzhou, east China's Zhejiang Province, May 23, 2018. Yan, 55, has worked in the national level ancient book restoration center of the library for 38 years. She and her colleagues collected more than 200 types of paper to restore ancient books. (Xinhua/Weng Xinyang)
Yan Jingshu (R) instructs an apprentice in ancient book restoration at Zhejiang Library in Hangzhou, east China's Zhejiang Province, May 23, 2018. Yan, 55, has worked in the national level ancient book restoration center of the library for 38 years. She and her colleagues collected more than 200 types of paper to restore ancient books. (Xinhua/Weng Xinyang)
Yan Jingshu restores an ancient book at Zhejiang Library in Hangzhou, east China's Zhejiang Province, May 23, 2018. Yan, 55, has worked in the national level ancient book restoration center of the library for 38 years. She and her colleagues collected more than 200 types of paper to restore ancient books. (Xinhua/Weng Xinyang)
Yan Jingshu dyes restoration paper at Zhejiang Library in Hangzhou, east China's Zhejiang Province, May 23, 2018. Yan, 55, has worked in the national level ancient book restoration center of the library for 38 years. She and her colleagues collected more than 200 types of paper to restore ancient books. (Xinhua/Weng Xinyang)
Yan Jingshu selects restoration paper at Zhejiang Library in Hangzhou, east China's Zhejiang Province, May 23, 2018. Yan, 55, has worked in the national level ancient book restoration center of the library for 38 years. She and her colleagues collected more than 200 types of paper to restore ancient books. (Xinhua/Weng Xinyang)
Yan Jingshu restores an ancient book at Zhejiang Library in Hangzhou, east China's Zhejiang Province, May 23, 2018. Yan, 55, has worked in the national level ancient book restoration center of the library for 38 years. She and her colleagues collected more than 200 types of paper to restore ancient books. (Xinhua/Weng Xinyang)
Photo taken on May 23, 2018 shows restoration paper notebooks at an ancient book restoration center of Zhejiang Library in Hangzhou, east China's Zhejiang Province. Yan, 55, has worked in the national level ancient book restoration center of the library for 38 years. She and her colleagues collected more than 200 types of paper to restore ancient books. (Xinhua/Weng Xinyang)