《汉书·志·礼乐志》
天气的精华，在云阳的都城回旋往返，经过很长时间，曰益茂盛，芝草具有灵气。
玄气之精，回复此都，蔓蔓日茂，芝成灵华。
The essence of weather, circling back and forth in the capital of Yunyang, after a long time, it became more and more prosperous, and Lingzhi grass had aura.