Musannaf Ibn Abi Shayba 3:1859

Hushaym narrated to us, he said: Ali bin Zayd bin Jud'an narrated to us, from Abu Rafi', who said: I prayed the last Isha prayer behind Abu Hurayrah in Medina. He said: He recited in it "When the sky has split asunder" (Surah Al-Inshiqaq) and prostrated in it. I said: "Do you prostrate in it?" He replied: "I saw my intimate friend, Abu al-Qasim (the Prophet), prostrate in it, so I will not abandon that."