《后汉书·列传·南匈奴列传》
四年，庞参升为大鸿胪，朝廷任命束平相宋汉接任度辽将军。
四年，庞参迁大鸿胪，以东平相宋汉代为度辽将军。
In the fourth year, Pang Can was promoted to Great Grand Minister of Ceremonies, and the imperial court appointed Song Han's assistant, Shu Pingxiang, as General of Liaodong.