The Book Pertaining to the Excellent Qualities of the Holy Prophet (may Peace be upon them) and His Companions (Kitab Al-Fada'il)
Muslim :: Book 30 : Hadith 5803
Abu Ishaq reported: I was sitting with 'Abdullah b. 'Utba and there was a discussion about the age of the Messenger of Allah (may peace be upon him). Some of the persons said: Abu Bakr was older than Allah's Messenger (may peace be upon him). 'Abdullah said: Allah's Messenger (may peace be upon him) died when he was sixty-three, and Abu Bakr died when he was sixty-three and so 'Umar fell as a martyr when he was sixty-three. A person from the people who was called 'Amir b. Sa'd reported that Jabir had said: We were sitting with Mu'awiya that there was a discussion about the age of Allah's Messenger (may peace be upon him). Thereupon Mu'awiya said: Allah's Messenger (may peace be upon him) died when he had attained the age of sixty-three, and Abu Bakr died when he had attained the age of sixty-three, and Umar fell as a martyr when he had attained the age of sixty-three.