遼史
According to the "History of Liao" compiled in the 14th century, a "sacred man" ("shen-ren") on a white horse had eight sons with a "heavenly woman" ("tiannü") who rode in a cart pulled by a grey ox. The man came from the Tu River (Lao Ha river in modern-day Jilin, Manchuria) and the woman from the Huang River (modern day Xar Moron river in Inner Mongolia). The pair met where the two rivers join, and the eight sons born of their union became eight tribes.