《论衡·卷二十九·案书篇》
汉代写书的人很多，司马迁、扬雄如黄河汉水一样博大渊深，其余的人不过像泾河渭河一样。
汉作书者多，司马子长、扬子云，河、汉也，其余泾、渭也。
In the Han Dynasty, there were many authors; Sima Qian and Yang Xiong were like the Yellow River and Han River, vast and profound. The rest of the authors were no more than Jing River and Wei River.