《资治通鉴·汉纪·汉纪十九》
太子太傅萧望之认为： 单于不奉汉朝正朔，本不是我国的臣属，所以称为匹敌之国，应不用臣属的礼仪对待他，使其位次在诸侯王之上。
太子太傅萧望之以为： 单于非正朔所加，故称敌国，宜待以不臣之礼，位在诸侯王上。
The Crown Prince's tutor Xiao Wangzhi believed that, since the Chanyu did not accept the Han’s reign title, and was not one of our empire’s vassals, he should be called a "peer state," and not treated with the ritual of vassals; he should be ranked above the princes.