《水经注·卷九》
水又往东流过清渊县老城西面，又流过县城西北，就是清渊，所以县名也就叫清渊县。
其水又东过清渊县故城西，又历县之西北为清渊，故县有清渊之名矣。
The river also flows east through the west of the old city of Qingyuan County, and then through the northwest of the county town, which is Qingyuan, and the county is named after it.