The Messenger of Allah ﷺ said, "The ears are part of the head." He would wipe his head once, and he would wipe the inner corners of his eyes.
حدثنا محمد بن زياد أنبأنا حماد بن زيد عن سنان بن ربيعة عن شهر بن حوشب
أن رسول الله ﷺ قال الأذنان من الرأس وكان يمسح رأسه مرة وكان يمسح المأقين
[Its chain is hasan] Abu Dawud narrated it in the Book of Purification, Chapter on the description of the Prophet's wudu, hadith no. 134, from the hadith of Hammad bin Zayd, with this wording. Shahr and his student have both been criticized, but their hadith does not fall below the level of hasan, and it has supporting narrations.