《史记·三十世家·田敬仲完世家》
苏代说： 东西两帝订立盟约进攻赵国有利，还是讨伐宋国的暴君有利？ 
曰： 两帝立约伐赵，孰与伐桀宋之利？ 
Su Dai said, "Is it better to make an alliance with the two emperors in the east and west to attack Zhao, or to punish the tyrant of Song?"