Ubaydullah bin 'Abdullah bin 'Utba عبيد الله بن عبد الله بن عتبة بن مسعود · The Book on the Two Eids

"Umar bin Al-Khattab asked Abu Waqid Al-Laithi what Allah's Messenger would recite during Al-Fitr and Al-Adha, so he said: 'He would recite: Qaf, By the Glorious Quran and the Hour has drawn near, and the moon has been cleft asunder.'"