Sahih Bukhari
Sahih Bukhari Volume 001, Book 004, Hadith Number 213.
Hadith Section/Book: Sahih Bukhari Sahih Bukhari Book 04. Ablutions (Wudu')
Narated By 'Amr bin 'Amir : Anas said, "The Prophet used to perform ablution for every prayer." I asked Anas, "What you used to do?' Anas replied, "We used to pray with the same ablution until we break it with Hadath."