Musnad Abu Ya'la al-Mawsili 109:12

Ishaq narrated to us, Hushaym narrated to us, from Abu Bishr, from Abu Sufyan, from Jabir, that the delegation of Thaqif asked the Prophet, peace and blessings of Allah be upon him, saying: "Our land is a cold land, so how should we perform the ghusl (full ritual bath)?" He said: "As for me, I pour three handfuls of water over my head."