《史记·三十世家·楚世家》
灵王说： 过去，我们远祖伯父昆吾住在原来的许国，今天郑国人贪婪地占据那块田地，不给我，现在我去要回，他们将给我吗？ 
灵王曰： 昔我皇祖伯父昆吾旧许是宅，今郑人贪其田，不我予，今我求之，其予我乎？ 
King Ling said: "In the past, our distant ancestor, our paternal uncle Kunwu, resided in the former State of Xu. Today, the people of Zheng are greedily occupying that land, not giving it to me. Now, if I go and ask for it back, would they give it to me?"