Yahya related to me from Malik from Ibn Shihab that he was askedabout the hadd of the slave for wine. He said, "I heard that he hashalf the hadd of a freeman for drinking wine. Umar ibn al-Khattab,Uthman ibn Affan, and Abdullah ibn Umar flogged their slaves with halfof the hadd of a freeman when they drank wine."
USC-MSA web (English) reference: Book 42, Hadith 3
Arabic reference: Book 42, Hadith 1542