《新唐书·列传·卷一百三十三》
相貌瘦弱丑陋，粗通文字与筹算，在高力士手下服侍，四十余岁时，让他主管养马的账务。
貌儜陋，略通书计。事高力士，年四十馀，使主厩中簿最。
He looked skinny and ugly and had a basic knowledge of literature and calculations and waited on Gao Lishi. At the age of forty or more, Gao Lishi let him manage the horse breeding books.