Abu Dawud
Purification (Kitab Al-Taharah)
Book Number: 001 / Hadith Number: 68
Narated By Abdullah ibn Abbas : One of the wives of the Prophet (pbuh) took a bath from a large bowl. The Prophet (pbuh) wanted to perform ablution or take from the water left over. She said to him: O Prophet of Allah, verily I was sexually defiled. The Prophet said: Water not defiled.