Muwatta Imam Malik (Riwayat Ibn al-Qasim)

And with the same chain of narration, it is narrated from Sayyiduna Anas bin Malik (may Allah be pleased with him) that milk mixed with (well) water was brought to the Messenger of Allah (peace and blessings be upon him). On his right was a Bedouin (villager) and on his left was Sayyiduna Abu Bakr Siddiq (may Allah be pleased with him). The Prophet (peace and blessings be upon him) drank (the milk), then gave (the remaining milk) to the Bedouin and said: "The right (has precedence), then (whoever is) on the right after him."