《宋书·志·卷十一》
现在的乐府铙歌是修改汉、魏时代原有的乐曲，虽然乐曲的名称有时是相同的，但文字是决不相同的，衹从研究文字入手探求其中的道理，没有一首可以得出结论。
今乐府铙歌，校汉、魏旧曲，曲名时同，文字永异，寻文求义，无一可了。
The present-day Naogo in the Yuefu is a revision of the original music of the Han and Wei dynasties. Although the names of the music are sometimes the same, the lyrics are definitely not the same. If we only study the lyrics to explore the underlying principles, we will not be able to draw any conclusions.