Sayyiduna Ibn Abbas (may Allah be pleased with them both) says that I have preserved all the Sunnahs of the Prophet (peace be upon him), but there are three things I do not know: The first is whether the Prophet (peace be upon him) used to recite (audibly) in Zuhr and Asr or not? And I also do not know how the Prophet (peace be upon him) used to pronounce this word: «وَقَدْبَلَغْتُمِنْالْكِبَرِعُتِيًّا» (with a dhamma on ‘Ain and with a Ta) or «عُسُيًّا» (with a dhamma on ‘Ain and with a Seen)? The third thing the narrator forgot.
Hadith Referenceمسند احمد / ومن مسند بني هاشم / 2332