Sahih Bukhari Volume 005, Book 058, Hadith Number 236.
Hadith Section/Book: Sahih Bukhari Sahih Bukhari Book 58. Merits of the Helpers in Madina (Ansaar)
Narated By Hisham's father : Khadija died three years before the Prophet departed to Medina. He stayed there for two years or so and then he married 'Aisha when she was a girl of six years of age, and he consumed that marriage when she was nine years old.