Jeongseon Lee clan
Jeongseon Lee clan () is one of the Korean clans. Their Bon-gwan is in Jeongseon County, Gangwon Province (historical). According to the research held in 2000, the number of Jeongseon Lee clan’s member was 3657. Their founder was who immigrated to Goryeo and was settled in Qìng Prefecture to avoid war with Jin dynasty (1115–1234) happened in Song dynasty period during Emperor Huizong of Song’s reign. was originally born as a third son in Lý dynasty, Vietnam when Nhân Tông of Lý dynasty, 4th emperor, ruled. However, he exiled himself to Song dynasty because he  was involved a political war. However, there are many doubts that Lee Yang gon is founder of Jeongseon Lee clan. According to "Đại Việt sử ký toàn thư", Nhân Tông of Lý dynasty has no children, and Thần Tông of Lý dynasty is not his son but his nephew. Therefore, the father-son relationship between Lee Yang gon and Nhân Tông and the brother relationship between Thần Tông are contrary to historical facts. As the "History of Song (book)" records that Thần Tông is the son of Nhân Tông, it is not ruled out that the descendants of the Lý  dynasty made up stories based on "History of Song (book)". According to his genealogy, Yi Ui-min was the sixth grandson of Lee Yang gon, and Yi Ui-min was already the seventh-ranked general at the time of the military coup in 1170. His age is estimated to be 20, and he has two elder brothers. It is unimaginable that Nhân Tông, born in 1066, would have to multiply six generations in more than 70 years, let alone his third son. If Lee Yang gon was indeed the younger brother of Thần Tông, it would be impossible to multiply  six generations in 20 to 30 years. According to his genealogy, Lee Yang gon had a grandson who served as the "ritual judgement" during Injong of Goryeo. This official position only appeared during the reign of King Gongmin.