《汉书·传·西域传下》
现在边塞的管制不严，对擅自出境的不能禁止，障候的官长驱使士卒打猎，以野兽的皮肉谋利，士卒劳苦，烽火事很少有人过问，这些情况，都不上报。后有来投降的，或是捉到俘虏，才知这些情况。
今边塞未正，阑出不禁，障候长吏使卒猎兽，以皮肉为利，卒苦而烽火乏，失亦上集不得，后降者来，若捕生口虏，乃知之。
Now the border controls are not strict, and those who go abroad without permission cannot be prohibited. The chief officer of the barrier drives the soldiers to hunt, and profits from the fur of the beasts, the soldiers are tired, and few people ask about the beacon fire, these situations are not reported. Later, when there were more people who came to surrender, or when they were captured, they learned about these situations.