《吕氏春秋·纪·孟秋纪》
立秋那天，天子亲自率领三公九卿诸侯大夫，到西郊去迎接秋的降临。
立秋之日，天子亲率三公九卿诸侯大夫，以迎秋于西郊。
On the day the autumn begins, the emperor personally leads the Three Dukes, Nine Ministers, feudal lords, and officials to the western outskirts to welcome the arrival of autumn.