Sahih Bukhari
Sahih Bukhari Volume 009, Book 091, Hadith Number 355.
Hadith Section/Book: Sahih Bukhari Sahih Bukhari Book 91. Accepting Information given by a Truthful Person
Narrated By 'Abdullah : The Prophet led us in Zuhr prayer and prayer five Rakat. Somebody asked him whether the prayer had been increased." He (the Prophet) said, "And what is that?" They (the people) replied, "You have prayed five Rakat." Then the Prophet offered two prostrations (of Sahu) after he had finished his prayer with the Taslim.