《资治通鉴·汉纪·汉纪五十二》
于是张杨允许曹操的使者通过河内郡前往长安，同时自己上表推荐曹操。
杨是通操上事，仍表荐操。
So Zhang Yang allowed Cao Cao’s envoy to pass through He Nei commandery to Chang An and at the same time himself recommended Cao Cao to the court.