《旧唐书·本纪·卷八》
夏四月二十七日，封契丹首领松漠都督李郁于为松漠郡王，奚首领饶乐都督李鲁苏为饶乐郡王。
夏四月丁酉，封契丹首领松漠都督李郁于为松漠郡王，奚首领饶乐都督李鲁苏为饶乐郡王。
On the 27th of the fourth month in summer, the Khitan leader Songmodudu, Li Yuyu, was granted the title of Prince of Songmodu, and the Xi leader Raoledudu, Li Lusu, was granted the title of Prince of Raole.