《北史·列传·卷四》
往昔在汉室之世，呼韩邪来叩边塞，汉派董忠、韩昌率领边郡人马，送出朔方，于是留下卫助。
昔汉宣之世，呼韩款塞，汉遣董忠、韩昌领边郡士马，送出朔方，因留卫助。
In the past during the reign of the Han, when Huhanye came to pay homage on the frontier, the Han government sent Dong Zhong and Han Chang to lead men from the border regions to accompany him to the north of the Shuo Fang commandery, who then remained there to help.