The Book of Prayers (Kitab Al-Salat)
Muslim :: Book 4 : Hadith 2041
Umm 'Atiyya reported: The Apostle of Allah (may peace be upon him) came to us when we were bathing his daughter, and he told us: Wash her with water and (with the leaves of) the lote tree, three or five times, or more than that if you think fit, and put camphor or something like camphor in the last washing; then inform me when you have finished. So when we had finished, we informed him, and he gave to us his (own) under-garment saying:" Put it next her body."