Tirmidhi 574

[Its isnad is sahih]. Nasai also reported it (2/161, hadith 965, Book of the Opening, Chapter on sujud in "When the Sky Splits Asunder") from Qutayba, through the same chain, and Sufyan bin Uyayna made clear that he heard it directly, as recorded by Humaydi (hadith 998). It is also found in Musnad Umar bin Abdul-Aziz by Baghandi (hadith 31).