《吕氏春秋·览·审应览》
魏上说； 我说 宁肯任用奴仆，也不用孟卯， 孟卯长叹道： 您受秦国控制是应该的了，秦国善待我，您对此为什么要猜疑呢？把绛、窃、安邑的地图让牛驮者献给秦国，秦国尚且会好好对待牛。
王何疑秦之善臣也？以绛、汾、安邑令负牛书与秦，犹乃善牛也。
Wei Shang said: I said I would rather appoint slaves than Meng Mao, Meng Mao sighed and said: You should be controlled by the Qin State. The Qin State treats me well. Why do you suspect this? I offered the maps of Jiang, Qie, and Anyi to the Qin State with a cow, and the Qin State even treated the cow well.