Sayyiduna Jubayr bin Mut'im (may Allah be pleased with him) narrated: We disputed about the ritual bath (ghusl) in the presence of the Messenger of Allah (peace and blessings be upon him), and the Messenger of Allah (peace and blessings be upon him) said: "As for me, I pour three handfuls of water over my head."
Hadith Referenceالمعجم الكبير للطبراني / باب الجيم / 1472