Musannaf Ibn Abi Shayba 3:5685

Ibn Idris and Ubayd Allah ibn Musa narrated to us, from Ubayd Allah ibn Abi Ziyad, who said: I recited the prostration (verse) while I was prostrating, so I asked Sa'id ibn Jubayr. He said: "It suffices you, and you should not recite while you are prostrating."