《太平广记·卷一百六十五·廉俭（》
郑浣见了又叹息又生气，对他说；饼皮和里面有什么区别，你竟然有这样轻浮狡诈的毛病，如此奢侈浪费，你应该保持淳朴的风俗习惯，我可怜你在家乡穿着破衣服出力务农，以为你一定会懂得种庄稼的辛苦，没想到你却轻浮得超过诸侯贵族家的绔绔子弟。
谓曰：皮之与中，何以异也？仆尝病浇态讹俗，骄侈自奉，思得以还淳反朴，敦厚风俗。是犹怜子力田弊衣，必能知艰于稼穑，奈何嚣浮甚于五侯家绮纨乳臭儿耶？
Zheng Ran sighed and became angry when he saw it. He said to him; What's the difference between the skin of the bread and the inside? You have such a frivolous and cunning problem. You are so extravagant and wasteful. You should maintain simple folk customs. I pity you for wearing torn clothes at home and working hard to farm. I thought you would definitely understand the hardship of growing crops, but I didn't expect you to be more frivolous than the dude children of the princes and nobles.