Ali bin Rabi'ah said: I was present with Ali bin Abi Talib (may Allah be pleased with him) on the day of Eid. I saw him wearing a turban; he had let the end of his turban hang down behind him, and the people did the same.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب صلاة العيدين / 6141