Yahya related to me from Malik from Ibn Shihab from Said ihn al-Musayyab that Umar ibn al Khattab and Uthman ibn Affan, may Allah be pleased with them, used to do the same. (ES)
USC-MSA web (English) reference: Book 9, Hadith 90 (ES)
Arabic reference (ES): Book 9, Hadith 422 (ES)