大越史記
The books "Đại Việt sử ký toàn thư" (from the 15th century) and "Lĩnh Nam chích quái" ("Wonders plucked from the dust of Linh-nam", from the 14th century) mention the legend. In "Đại Việt sử ký toàn thư" Âu Cơ is the daughter of Đế Lai (also known as Đế Ai 帝哀, or Emperor Ai, who was a descendant of Shennong), while in "Lĩnh Nam chích quái" she is the wife of Đế Lai. Ngô Sĩ Liên commented in the "sử ký" on the somewhat primitive nature of the relationship between the two progenitors, given that Lạc's father Kinh Dương Vương and Âu's grandfather Đế Nghi were brothers. The story of Âu Cơ and Lạc Long Quân is taught widely in Vietnamese schools.