Sahih Muslim Book 031, Hadith Number 5876.

Chapter : The merits of Abu Bakr Siddiq (Allah be pleased with him).

'Amr b. Al-'As reported that Allah's Messenger (may peace be upon him) sent him in command of the army despatched to Dhat-as-Salasil. When 'Amr b. al-'As came back to the Holy Prophet (may peace be upon him) he said: Who amongst people are dearest to you? He said: 'Aisha. He then said: Who amongst men? He said: Her father, and I said: And who next? He said: Umar. He then enumerated some other men.