《北史·本记·卷二》
到达受降城以后，不见蠕蠕的踪影，便在城内屯积粮食，留下军队守护，然后回军。
至受降城，不见蠕蠕，因积粮城内，留守而还。
After arriving in Shouxiang City, they did not see any sign of the Rouran people. After stockpiling food in the city and leaving an army to guard it, the army returned.