《资治通鉴·唐纪·唐纪六十二》
武宗又问宰相，李德裕认为： 鸟飞不动了落到人的怀里，尚且应当保护存活，何况回鹘帮助国家平定安史之乱，多次立有大功。
上以问宰相，李德裕以为： 穷鸟入怀，犹当活之。
Emperor Wuzong then asked the prime minister. Li Deyu stated: "When a bird is unable to fly and falls into someone's arms, it should be cared for and kept alive. The Huihu have assisted the state in pacifying the Anshi Rebellion and made numerous contributions."