《汉书·传·李广苏建传》
苏武与副使汉中郎将张胜以及临时兼任使者属吏的常惠等人招募士卒、斥候一百多人同去匈奴。
武与副中郎将张胜及假吏常惠等募士斥候百余人俱。
Su Wu, together with the deputy envoy, imperial bodyguard of Hanzhong Zhang Sheng, and others, including Chang Hui who temporarily assumed duty as a subordinate of the envoy, recruited over a hundred soldiers and scouts to go to Xiongnu.