《资治通鉴·汉纪·汉纪十三》
曾经出使大宛的姚定汉等奏道： 大宛军事力量薄弱，只要派去三千人马，用强弩射杀，就可将其全部俘获。 
诸尝使宛姚定汉等言： 宛兵弱，诚以汉兵不过三千人，强弩射之，可尽虏矣。 
Yao Dinghan and others who had been sent to Dayuan played the memorial: Dayuan's military strength is weak. As long as 3,000 troops are sent to shoot them with strong crossbows, they can be captured.