《资治通鉴·唐纪·唐纪五十五》
当时，圆净已经有八十多岁，捉拿敌人的官兵得到圆净后，用子猛打他的小腿，但并不能将他的小腿打断。
圆净时年八十馀，捕者既得之，奋锤击其胫，不能折。
At that time, Yuanjing was already in his eighties. After the official soldiers captured him, they used clubs to beat his calves, but they couldn't break them.