《汉书·传·匈奴传上》
第二年春天，汉朝君臣商议： 翕侯赵信给单于献计谋，迁居到大漠以北，认为汉军攻不到那裹。 
其明年春，汉谋以为 翕侯信为单于计，居幕北，以为汉兵不能至 。
In the spring of the next year, the Han dynasty officials and the Emperor discussed: Marquis of Xi, Zhao Xin, suggested a strategy to the Chanyu to move north of the great desert, believing that the Han army would not be able to attack there.