《资治通鉴·晋纪·晋纪三十四》
杜弘说： 我到长安之后，如果找不到太后，不能了解太后们的身体生活等情况，那么，我会向西再到张掖去打听，尽全力完成任务，一直到死。
弘曰： 臣至长安，若不奉太后动止，当西如张掖，以死为效。
Du Hong said: “When I arrive in Chang’an, if I am unable to find Empress Dowager and to learn of their health and well-being—then I will go west to Zhangye to make inquiries. I will use up all of my strength to fulfill this mission, even if it means death.