Chapter 1: Purification (Kitab Al-Taharah)
Narrated Abu Rafi': One day the Prophet (ﷺ) had intercourse with all his wives. He took a bath after each intercourse. I asked him: Messenger of Allah, why don' t you make it a single bath? He replied: This is more purifying, better and cleaning. Abu Dawud said: The tradition narrated by Anas is more sound that this tradition.
Sunan Abi Dawud 219