《三国志·魏书·张乐于张徐传》
高幹坚守壶关，乐进没有能攻克，适逢太祖亲自率军前来征讨，才攻占了壶关。
幹坚守未下，会太祖自征之，乃拔。
Gao Gan held out at Huguankou Pass, and Yue Jin was unable to break through. It was only when Cao Cao himself arrived with reinforcements that the pass was captured.