《汉书·传·儒林传》
关内侯郑宽中有颜子的美好品质，包容商、偃的文学，总括《五经》的妙论，立于师傅的显赫位置，在内则追随唐虞大道，向天子陈述圣王之法，在外则参与冢宰要职，功劳扩大到处理政事上，减退所食之禄，从至公之道，不自开私门，分散赐给九族。田亩不增加，德行与周召相配，忠心与《羔羊》相合，没能升任司徒，拥有家臣，猝然早逝，更可哀痛！
关内侯郑宽中有颜子之美质，包商、偃之文学，严然总《五经》之眇论，立师傅之显位，入则乡唐、虞之闳道，王法纳乎圣听，出则参冢宰之重职，功列施乎政事，退食自公，私门不开，散赐九族，田亩不益，德配周、召，忠合《羔羊》，未得登司徒，有家臣，卒然早终，尤可悼痛！
Guan Neihou Zheng Kuangzhong had the good character of Yanzi, possessed the literature of Shang and Yan, summed up the wonderful theories of the Five Classics, stood in the prominent position of a teacher, followed the great way of Tang and Yu in politics, and stated the ways of the Saint King to the emperor. Externally, he participated in the important position of the Grand Minister, his achievements extended to handling political affairs. He reduced the income of his food, and practiced the way of acting for the public good, did not set up his own party, and distributed the favors to his nine tribes. The land did not increase, his moral character was equal to that of Zhou and Zhao, and his loyalty was in line with that of "Lamb". He failed to be promoted to Sikou, to have retainers, and to die unexpectedly, which is even more regrettable!