《后汉书·列传·伏侯宋蔡冯赵牟韦列传》
今京师空匮，资用不足，未能服近而先征边外；且渔阳之地，逼近北狄，彭宠困迫，必求其助。
今京师空匮，资用不足，未能服近而先事边外；且渔阳之地，逼接北狄，黠虏困迫，必求其助。
But at present the capital is short of supplies and funds, and you cannot pacify the areas close at hand and yet at the same time go and attack those far away. Moreover, Yuyang is near to the Northern Barbarians, and since Peng Chong is hard pressed, he will certainly seek their help.