Musnad Ahmad 962:173

Yahya ibn Ishaq narrated to us, Hammad ibn Zayd informed us, from Sinan ibn Rabi'ah, from Shahr—meaning Ibn Hawshab—from Abu Umamah: "The Prophet, peace and blessings of Allah be upon him, performed ablution (wudu). He rinsed his mouth three times, inhaled water into his nose three times, and washed his face, and he used to wipe the corners of the eyes." He said: "And the Prophet, peace and blessings of Allah be upon him, used to wipe his head once, and he used to say: 'The ears are part of the head.'"