Bai Juyi,
The Song of Everlasting Regret
“ The soldiers of the imperial guard took this opportunity to proclaim that Yang Guozhong was planning treason along with the Tufan emissaries, and they killed him, along with his son Yang Xuan (楊暄) , the Ladies of Han and Qin, and the official Wei Fangjin. Chancellor Wei Jiansu was also nearly killed, but was spared at the last moment with severe injuries. The soldiers then surrounded Emperor Xuanzong's pavilion, and refused to scatter even after Emperor Xuanzong came out to comfort them and order them to disperse. ”
