Sunan an-Nasa'i, Book 1, Hadith 189 (In-Book) ⓘ
It was narrated from Qais bin 'Asim that he accepted Islam, and the Prophet commanded him to perform Ghusl with water and lotus leaves.
أَخْبَرَنَا عَمْرُو بْنُ عَلِيٍّ، قَالَ حَدَّثَنَا يَحْيَى، قَالَ حَدَّثَنَا سُفْيَانُ، عَنِ الأَغَرِّ، - وَهُوَ ابْنُ الصَّبَّاحِ - عَنْ خَلِيفَةَ بْنِ حُصَيْنٍ، عَنْ قَيْسِ بْنِ عَاصِمٍ، أَنَّهُ أَسْلَمَ فَأَمَرَهُ النَّبِيُّ صلى الله عليه وسلم أَنْ يَغْتَسِلَ بِمَاءٍ وَسِدْرٍ .
also referenced under: Volume 1, Book 1, Hadith 188 (DarusSalam)