《史记·三十世家·晋世家》
里克进谏献公说： 太子是奉献祭祀宗庙、社稷的祭品、早晚检查国君膳食的人，所以叫冢子。
里克谏献公曰： 太子奉冢祀社稷之粢盛，以朝夕视君膳者也，故曰冢子。
Li Ke advised Duke Xian: The crown prince is the sacrifice to the ancestral temple and the altar of the land and grain, and the person who checks the diet of the monarch in the morning and evening, so he is called Zhong Zi.