Sahih Muslim Book 8, Hadith Number 3398.
Chapter: Kitab Al-Rada’a-Book pertaining to fosterage.
‘Aisha (Allah be pleased with her) reported: There came to me Aflah b. Abu Qulais, my uncle by reason of fosterage; the rest of the hadith is the same (but with this) addition: “I (‘Aisha) said (to the Holy Prophet): It was the woman who suckled me and not the man, whereupon he (Allah’s Messenger) said: May your hands or your right hand be besmeared with dust (you were mistaken).”