《论衡·卷十五·变动篇》
这大约是北方三月还在寒冷，霜恰好自天而降，而邹衍正好仰天长叹，与降霜碰到一起。
此殆北边三月尚寒，霜适自降，而衍适呼，与霜逢会。
It was probably still cold in March and it just so happened that frost came down from the sky as Zou Yan happened to look up to the sky and sigh.