《旧唐书·本纪·卷八》
三日，皇上到北都巡行境内，命所到之处慰问老年人、老而无妻、老而无夫、老而无子、无兄弟者以及外出从军的人家；流放、死罪减免一等。另外改变旧宅为飞龙宫。
庚辰，幸并州、潞州，宴父老，曲赦大辟罪已下，给复五年。别改其旧宅为飞龙宫。
On the third day, the emperor visited the territory of Bei-du (North Capital) and ordered that the elderly, the widowed, the childless, the orphaned, and those who had gone out to serve in the military be comforted; exiles and capital convicts were reduced by one grade. In addition, the old mansion was changed to Fei-long (Flying Dragon) Palace.