Sahih Bukhari Volume 007, Book 063, Hadith Number 207.
Narrated By Al-Aswad : 'Aisha intended to buy Barira, but her masters stipulated that her wala wound be for them. 'Aisha mentioned that to the Prophet who said (to 'Aisha), "Buy and manumit her, for the wala is for the one who manumits." Once some me; was brought to the Prophet and was said, "This meat was given in charity to Barira. " The Prophet said, "It an object of charity for Barira and present for us."