《文心雕龙·杂文》
正如扬雄所说：这是首先 大肆宣扬郑国和卫国的淫乐，曲子末了才缀以典正的雅乐 。
子云所谓 犹骋郑卫之声，曲终而奏雅 者也。
As Yang Xiong said: This is to first of all vigorously publicize the lewd music of Zheng and Wei, and then add the orthodox elegant music at the end of the song.