Bukhari :: Book 7 :: Volume 69 :: Hadith 523

Narrated Anas bin Malik:

Milk mixed with water was brought to Allah's Apostle while a bedouin was on his right and Abu Bakr was on his left. He drank (of it) and then gave (it) to the bedouin and said, 'The right" "The right (first)."

Source materials are from the University of Southern California MSA site
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