《旧唐书·列传·卷六十七》
于是杀死了他的儿子，将用诚摔在地上，壮兵坐在他肚子上，用刀尖抵住他的喉咙说： 出声即死！ 
遂格杀其子，而仆用诚于地。壮士跨其腹，以刃拟其喉曰： 出声即死！ 
Then they killed his son, threw Yongcheng on the ground, the soldiers sat on his stomach, and held the tip of the knife against his throat and said: If you make a sound, you will die!