The Book of Marriage (Kitab Al-Nikah)

Muslim :: Book 8 : Hadith 3409

Ibn Abbas (Allah be pleased with them) reported: It was proposed that he (the Holy Prophet) be married to the daughter of Hamza, whereupon he said: She is not lawful for me for she is the daughter of my foster-brother, and that is unlawful by reason of fosterage what is unlawful by reason of genealogy.

Source materials are from the University of Southern California MSA site
Hadith eBooks converted from Imaan Star