Umar bin Aban bin Mufaddal al-Madani (may Allah have mercy on him) narrates: Sayyiduna Anas bin Malik (may Allah be pleased with him) showed me the ablution. He took a small leather water vessel (rakwah) and placed it on his left side, then poured water on his right hand and washed it three times. Then he tilted the rakwah over his right hand, taking water, and performed ablution, washing (the limbs) three times each, and wiped his head three times, and took fresh water for the openings of his ears and wiped their openings. I said to him: "You have wiped your ears as well?" He said: "O boy, they are part of the head; they are not part of the face." Then he said: "O boy, have you seen and understood, or shall I show you again?" I said: "This is enough for me, and I have understood." He said: "This is how I saw the Messenger of Allah (peace and blessings be upon him) performing ablution."
Imam al-Tabarani (may Allah have mercy on him) said: "Umar bin Aban did not narrate any hadith from Sayyiduna Anas (may Allah be pleased with him) other than this one."
A scholarly note about an edition: in the Dar al-Haramayn printed edition the words are (fa-ghasalahuma), whereas the confirmed wording has been taken from al-Tahhan's edition; it is also so in Majma' al-Bahrayn, and it is what fits the context. And Allah knows best.
Hadith Referenceالمعجم الأوسط / باب الجيم / 3362
Hadith Gradingمحدثین:إسناده ضعيف لجهالة عمر بن أبان
Hadith Takhrij«قال الهيثمي: قال الذهبي وعمر بن أبان لا يدرى من هو قلت ذكره ابن حبان في الثقات «مجمع الزوائد ومنبع الفوائد، ج 1، ص 235»» «قال ابن رجب الحنبلي: إسناده فيه جهالة «فتح الباري شرح صحيح البخاري لابن رجب، ج 1، ص 296»» «قال الذهبى: عمر بن أبان لا يدرى من هو والحديث ثماني لنا على ضعفه «لسان الميزان، ج 2، ص 452»» «أخرجه الضياء المقدسي فى «الأحاديث المختارة» برقم: 1866، 1867، 2117، والدارقطني فى «سننه» برقم: 370، والبزار فى «مسنده» برقم: 6671، والطبراني فى «الصغير» برقم: 76، 322، والطبراني فى «الأوسط» برقم: 1571، 2905»