Sa’ib bin Yazid says: On one occasion, Sayyiduna Uthman (may Allah be pleased with him) recited Surah Sad, and when he reached the verse of prostration, he also performed the prostration.
Hadith Referenceمسند احمد / مسند الخلفاء الراشدين / 541
Hadith Gradingحکم دارالسلام:صحيح، سويد بن سعيد متابع