律相感通傳 1.36

1.36

「答云：『在秦都城南二十里，有蒼頡造書臺，即其地也。』又云：『在沙河南五十里，青山北四十里。』

"He answered, 'Twenty li south of the Qin capital is the terrace where Cangjie created writing; that is the site.' He also said, 'It is fifty li south of the Sha River and forty li north of the Green Mountains.'"