《资治通鉴·唐纪·唐纪十八》
许敬宗的孙子太子舍人许彦伯指责袁思古与许家有私怨，请求改定别的谥号。
敬宗孙太子舍人彦伯讼思古与许氏有怨，请改谥。
Xu Jingzong's grandson, Crown Prince's Attendant, Xu Yanbo, accused Yuan Sigu of holding a personal grudge against the Xu family and requested that another posthumous name be chosen.