《资治通鉴·唐纪·唐纪六十二》
例如德宗在他晚年的时候，只信任裴延龄一人，其它宰相不过在朝廷的敕书中签名而已。这是当时朝政紊乱的主要原因。
如德宗末年，所听任者惟裴延龄辈，宰相署敕而已，此政事所以日乱也。
For example, in his later years, Dezong only trusted Pei Yanling, and the other prime ministers only signed the imperial edicts in the court. This was the main reason for the chaos in the government at that time.