The 'Jiriji' (Geography) of the "Samguk Sagi", history books in China, or The Shoku Nihongi mention Dongmyeong (동명; 東明), Wutae (우태; 優太), Gutae (구태; 仇太), and Domo (도모; 都慕).
[2] According to the inaugural year of King Onjo's accession in The 'Baekje Bongi' 1 of the "Samguk Sagi" Volume 23, Onjo's father was Chumo (추모; 鄒牟) or Jumong (주몽; 朱蒙), who came from Bukbuyeo to Jolbonbuyeo and married the second daughter of King of Buyeo.
However, when the son Jumong gave birth to when he was in Bukbuyeo came and became the crown prince, Onjo and Biryu left south with ten servants including Ogan (오간; 烏干) and Maryeo (마려; 馬黎) to Hansan (한산; 漢山).
Upon the arrival of his son Yuryu (유류; 孺留), born in Buyeo, Jumong made him the crown prince to succeed to the throne.
In response, Biryu, along with his younger brother Onjo, took his mother and crossed Paesu and Daesu to live in Michuhol.
On the other hand, according to Buksa and Suseo, Gongsun Du, the governor of Liaodong of the Han Dynasty, made Gutae, a descendant of Dongmyeong, who had a strong sense of dignity and trust, take his daughter as his wife.
Gakhun(覺訓)'s "Haedong Goseungjeon" describes Biryu as 'Piryu' (피류; 避流) and Onjo as 'Eunjo' (은조; 殷祚).