Yahya related to me from Malik from Yahya ibn Said that A'isha,the wife of the Prophet, may Allah bless him and grant him peace,said, "I saw three moons fall into my room, and I related my vision toAbu Bakr as-Siddiq. Then, when the Messenger of Allah died, may Allahbless him and grant him peace, and was buried in my house, Abu Bakrsaid to me, 'This is one of your moons, and he is the best of them.' "
USC-MSA web (English) reference: Book 16, Hadith 30
Arabic reference: Book 16, Hadith 552