Analysis of information sources in references of the Wikipedia article "Hand fan" in English language version.
The Japanese developed the folding fan, the Akomeogi, during the sixth century. Portuguese traders introduced it to the west in the 16th century and soon both men and women throughout the continent adopted it.
In the 7th century the folding fan evolved, the earliest form of which was a court fan called the "Akomeogi", which had thirty-eight blades connected by a rivet; it had artificial flowers at the corners and twelve long, colored silk streamers.
The first folding fan arrived as a tribute that was brought to China by a Japanese monk in 988. Writings of both Japanese and Chinese scholars concerning the folding fan, which was believed to have been first invented in Japan, apparently suggest that it received its shape from the design of a bat's wing.
Another Japanese creation enjoyed great success among foreigners: the folding fans. It was invented in Japan in the eighth or ninth century, when only round and fixed (uchiwa) fans made of palm leaves were known. -- their usage had spread throughout China in antiquity. Two types of folding fans developed: one was made of cypress-wood blades bound by a thread (hiogi); the other had a frame with fewer blades which was covered in Japanese paper and folded in a zigzag patterns (kawahori-ogi)."The paper fan was described by a thirteenth-century Chinese author, but well before that date Chōnen had offered twenty wooden-bladed fans and two paper fans to the emperor of China."
It was recorded in the Song Shu [sic.: the Song Sui is the correct source], the official history of the Chinese Song dynasty (960-1279), that in 988 a Japanese monk, Chonen, presented at court gifts of..."There are also numerous references to folding fans in the great classical literature of the Heian period (794-1185), in particular the Genji Monogatari (The Tale of Genji) by Murasaki Shikibu and the Makura no Sōshi (The Pillow Book) by Sei Shōnagon. Already by the end of tenth century, the popularity of folding fans was such that sumptuary laws were promulgated during Chōho era (999-1003) which restricted the decoration of both hiogi and paper folding fans."
Guo Ruoxu, for example, has included a short note about the folding fan in his Tuhua Jian Wen Zhi (Records of Paintings Seen and Heard About, 1074) It states that Korean envoys often brought along Korean folding fans as gifts. They were, Guo also pointed out, of Japanese origin.
In origin it was evidently Japanese, common already in the Heian period. A fragment of a late Heian folding-fan was excavated some decade ago at Takao-yama. Japanese fans were well known in China during the late eleventh century.