《汉书·纪·昭帝纪》
三年春季正月，泰山有大石自行起立，上林苑有柳树枯萎又重新长出绿叶。
三年春正月，泰山有大石自起立，上林有柳树枯僵自起生。
In the first month of spring in year three, a large rock stood up by itself on Mount Tai, and a withered willow tree in the Shanglin Garden sprouted green leaves again.