Musnad Ahmad 1173:4

Waki' narrated to us, he said: Sufyan narrated to us, from Abdullah ibn Muhammad ibn Aqil, from al-Rubayyi' bint Mu'awwidh ibn Afra', she said: "The Messenger of Allah (peace and blessings of Allah be upon him) came to us, so we placed the water vessel for him. He performed ablution three times each, and he wiped his head twice, beginning from the back of it, and he inserted his two fingers into his ears."