《资治通鉴·唐纪·唐纪五十九》
占卜算命人杜景先请求敬宗允许自己前往江淮、岭南各道，历遍各州，为敬宗求访有特殊才能异人。
山人杜景先请遍历江、岭，求访异人。
Fortune teller Du Jingxian asked Emperor Jingzong to allow him to go to various regions in Jiang淮 and Lingnan to search for people with special abilities.