《宋书·志·卷二十九》
大明二年五月甲子曰，山阳县舍有二只白燕，南兖州刺史竟陵王刘诞献上朝廷。
大明二年五月甲子，白燕二产山阳县舍，南兗州刺史竟陵王诞以献。
On the day of Jiazi in May of the second year of the Damming era, two white swallows appeared at the county house in Shanyang; Liu Dan, the governor of South Yanzhou and the king of Jingling, presented them to the imperial court.