大唐西域記 5.10

5.10

城西北窣堵波，無憂王之所建也。如來在昔，於此七日說諸妙法。其側則有過去四佛坐及經行遺迹之所。復有如來髮、爪小窣堵波。

To the north-west of the capital there is a stupa built by Asoka-raja. In this place Tathagata, when in the world, preached the most excellent doctrines for seven days. By the side of this stupa are traces where the four past Buddhas sat and walked for exercise. There is, moreover, a little stupa containing the relics of Buddha's hair and nails; and also a preaching-place.