《列子·汤问》
即使是师旷弹奏的清角，邹衍吹奏的声律，也不能超过你，他们将挟着琴弦、拿着萧管跟在你后面向你请教了。 
虽师旷之清角，邹衍之吹律，亡以加之。彼将挟琴执管而从子之后耳。 
Even the clear horn played by Shi Kuang and the melody blown by Zou Yan cannot surpass yours, they will hold their zithers and flutes and follow you to ask for your guidance.